THE CLASSIC: Flexion Contracture of the Knee: The Mechanics of the Muscular Contracture and the Turnbuckle Cast Method of Treatment; with a Review of Fifty-Five Cases: * : Clinical Orthopaedics and Related Research®

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SECTION I: SYMPOSIUM: Papers Presented at the Annual Meetings of the Knee Society

THE CLASSIC: Flexion Contracture of the Knee

The Mechanics of the Muscular Contracture and the Turnbuckle Cast Method of Treatment; with a Review of Fifty-Five Cases*

Kulowski, Jacob MD

Editor(s): Pagnano, Mark W MD

 J Bone Joint Surg Am

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Clinical Orthopaedics and Related Research 464():p 4-10, November 2007. | DOI: 10.1097/BLO.0b013e31815760ca
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Dr. Mark Pagnano, the Guest Editor of the Proceedings of The Knee Society, has suggested we republish Jacob Kulowski's account of correcting knee flexion contractures using a turnbuckle cast. This account is an excellent example of the best clinical research reporting of the time (1932). His concepts were three-dimensional, they were based upon surgical and autopsy findings and well-reasoned, and he carefully documented the clinical situations and amount of correction in 55 cases.

Kulowski described a gradual approach to the three-dimensional correction of knee flexion contractures using casting and a turnbuckle system based on those described by previous authors. His approach was based upon one described 10 years earlier by Mommsen (“Die Dauerwirkung kleiner kräfte bei der kontrakturbehandlung [quengel methode]” or, “The continuous effect of small forces on contracture treatment [quengel method]”).4 (“Quengel” evidently meant continuous application of small forces as with a turnbuckle, although it is not a word I can find in contemporary German dictionaries, including scientific.) Correction, Kulowski suggested, should be accomplished only within the tolerance of the patient, but he noted some patients did their own corrections at home. Further, among the 55 patients with 77 knee contractures, he reported correction in all but eight cases, three of whom were still under treatment. With average durations of contractures of differing etiologies varying from 2 to 3½ years and average contractures varying from 30-40°, he was able to achieve correction within 14-21 days.

Among this collection of papers presented at the Knee Society meeting, Ulrich et al5 report knee flexion contracture as the most common cause of a functionally-deficient knee following TKA. They describe a multimodal program of intensive physiotherapy, including a custom extension splint, for correcting contractures and achieved successful correction in three of 36 patients, not dissimilar from Kulowski's report of correction in all but eight of 77 cases.

Jacob Kulowski was born in Odessa, Russia, in 1900 and died in St. Joseph, Missouri, in 1982. He trained with Dr. Arthur Steindler at the University of Iowa in the 1930s, and published a number of papers based on material at the University. He subsequently went into private practice in St. Joseph, Missouri, where he met his wife-to-be, Margaret Snodgrass. Although he maintained a private practice, he continued to write prolifically until 1972 on topics as varied as osteomyelitis, Gaucher's Disease, metal implant corrosion, and flexion contracture of the knee, this month's Classic. During the late 1940s, Kulowksi developed a strong interest in injuries from car crashes, and published dozens of papers on the subject in addition to several books, including an exhaustive (1080 page) survey of the knowledge of automotive crashes.3 He edited an extensive three-part CORR symposium entitled, “Motorist Injuries and Motorist Safety,” in 1957 (see 50 Years ago in CORR in this issue).1 When as an expert he was interviewed by Time Magazine in 1953, the reporter noted, “State police officers recommended that motorists wear safety belts and crash helmets. But Dr. Jacob Kulowski of St. Joseph, Mo. took a more radical line. Much of the trouble, he insisted, is the design of automobiles, and he showed horror pictures to prove it, with front-seat passengers most often the victims. Automakers, he said, should pad the dashboard and get rid of the face-smashing projections which now make it as deadly as a shark's-tooth club.”2

References

1. Brand RA. 50 years ago in CORR: motorist injuries and motorist safety: introduction: prevention of accidents by Jacob Kulowski, MD. Clin Orthop Relat Res. 2007;464:253-255.

2. Drinks and dashboards. Time Magazine. Dec 14, 1953.

3. Kulowski J. Crash Injuries: The Integrated Medical Aspects of Au tomobile Injuries and Deaths Springfield, MO: Charles C. Thomas; 1960.

4. Mommsen F. Die Dauerwirkung kleiner kräfte bei der kontraktur behandlung (quengelmethode). Ztschr Orthop Chir. 1922.

5. Ulrich SD, Bhave A, Marker DR, Seyler TM, Mont MA. Focused rehabilitation treatment of poorly functioning total knee arthroplasties. Clin Orthop and Relat Res. 2007;464:138-145.

Richard A. Brand, MD

Editor-in-Chief

Flexion contracture of the knee, like all other similar situations of the body involving the muscles, bones, joints, and ligaments, is subordinate to the same biophysical laws enunciated by Steindler in relation to the wrist and fingers. Its analysis involves a consideration of the concomitant gliding and rotatory motions of the joint that are an essential part of the normal mechanics of flexion.

The knee is the largest and most complicated joint of the body. It is a trocho-ginglymus, and allows rotation about a vertical axis, as well as flexion and extension. “Its peculiar anatomic construction is an expression of the very exacting static and dynamic requirements which it must meet, because of its situation between the hip and ankle joints in the middle of the weight-supporting lower extremity” (Steindler). It will be shown that the abnormal new point of muscular equilibrium, which is the position of contracture, is dependent upon the normal mechanics of the knee, and follows definite physical laws.

Flexion contracture of the knee presents postural deviations in the three cardinal planes of the body, as a rule. In the sagittal plane there is the predominant flexion position and the usual posterior subluxation of the tibia on the femur. The frontal plane abnormality expresses itself in increased valgus, while the external rotation of the tibia takes place in the horizontal plane.

1. The Situation in the Sagittal Plane:

The mid-position of the knee is in moderate flexion, in which attitude the muscles about the joint are nearest their point of equilibrium. There is then an inherent tendency of the joint to assume flexion, especially during relaxation. In full extension the hamstrings are under a stretch and are, for that reason, in the optimum condition for contraction. Reflex irritation therefore anticipates prevailing action of the hamstrings.

Clinically, and by hydrostatic experiments, it is known that the greatest capacity of the knee joint capsule is in the position of flexion. Excessive amounts of fluid in the joint will then naturally dictate the flexion posture.

In flexion of the knee the initial twenty degrees is a pure rocking motion, and is completed by a gliding motion of the tibia upon the femur. Subluxation of the tibia, therefore, occurs at some point of the gliding range of the joint.

2. The Situation in the Frontal Plane:

The knee normally has an appreciable valgus. Any increase of this angle is associated with the mechanogenesis of pathological external rotation. The tensor fasciae and the biceps femoris are external rotators of the knee; contracture of either or both tends also to increase the valgus.

The peripheral resistance incident to weight-bearing in the usual externally rotated position upon a flexed knee tends to increase the valgus. This is also remarkable in knee joints that have been fused by operation in the position of flexion. Many of these develop a valgus deformity, especially in children. A “closed kinetic chain” may result even from recumbency, because of the usual attitude of inward rotation of the thighs assumed by arthrities, who have more or less involvement of the lower extremity.

3. The Situation in the Horizontal Plane:

The biceps femoris acts upon the tibia through a longer lever arm than the internal hamstrings, because it is more distally inserted from the center of rotation of the knee, the vertical axis of which passes through the medial condyle of the tibia. The moment of the externally rotating forces is then the greater. Other factors favoring external rotation during flexion are: the relaxation of the ligamentous structures, the unwinding action of the crucial ligaments, and the loose attachment of the external meniscus.

It is, therefore, evident that the key to the contracture complex is the flexion position. The associated elements are secondary phenomena directly dependent upon it. The contracture position is, therefore, a fixed exaggeration of the normal flexion mechanics of the knee, incident to the newly established muscular equilibrium, and is certainly not a haphazard event.

Clinically, the contractures of the knee may be classified as:

  1. Arthrogenic. This is by far the largest group as well as the most important one to be considered. Here are included all the contractures due to some primary joint pathology. The reflex irritations and hydrostatics are the predominant causes of deformity.
  2. Hypertonic. Muscular imbalance, due to increased innervational impulses as in spastic paralysis and similar conditions, is the causal factor in this group.
  3. Paralytic. This type is primarily due to muscular imbalance following paralysis or weakness of the antagonistic group, which in this case is the quadriceps. It may also be secondary to hip and ankle deformities.
  4. Congenital
  5. Postural. These are secondary, due to static causes brought on by flexion contracture of the hip and disturbances of gastrocnemius function.
  6. Myositic. This group is rare but may follow in the wake of histopathological changes in the muscles from actual inflammatory involvement of the muscles.

The method of gradual correction of flexion contractures of the knee is indicated in the great majority of cases, and is actually effective. This view is amply supported by clinical and experimental observations upon muscular contracture. However, nothing is known of the biophysical properties of the capsular, nervous, and vascular structures which play such a prominent rôle in the posterior part of the knee. This naturally limits the application of conservative methods.

The importance of the posterior capsule in certain contractures of the knee cannot be overemphasized. Silver very aptly designated all the soft structures of the joint as the “surgical capsule”.

Clinically, the block due to capsular shrinkage can be determined by the presence of a posterior springy resistance against passive extension of the knee in the presence of relaxed hamstrings. This has been confirmed at operation. In several such instances the complete relaxation of the muscles in the face of a markedly contracted capsule was remarkable. The muscles and tendons contiguous to the capsule do exhibit some shrinkage, while those more superficially placed are actually flaccid, even though they are a part of the same functional group. This is particularly true of the semimembranosus, because it has several broad aponeurotic insertions in and about the capsule. Similar observations, in principle, have been made in contractures of the hip joint.

The writer is convinced that capsular involvement precludes the mechanical method of correction by the present means at our disposal. In such cases the stripping of the capsule by the method of Silver or Wilson yields excellent results. Fortunately the capsule is, in most cases, the last structure to take part in the contracture. It is the writer's opinion that posterior capsular shrinkage does not occur in pure myogenetic contractures unless a very long period has elapsed. Among the many tenotomies that have been performed in this clinic, surprisingly few cases required additional capsulotomy. Actual inflammatory involvement of the capsule is the usual cause of capsular contracture, and such changes have been described in the literature.

Regarding the vascular and nervous structures even less can be said. If these cannot be accommodated to full extension, all corrective measures must be abandoned, save those that will shorten the extremity, as joint resection. But clinical experience teaches that, in practically all cases, these do respond to gradual correction.

Steindler called attention to the hypertrophied infrapatellar fat pad as a primary cause of flexion deformity, and anterior mechanical block to extension. In reviewing about sixty synovectomies performed in this clinic, the writer noted twelve cases of flexion contracture that resulted in full extension following operation.

The contra-indications to conservative gradual correction may be summed up as follows: (1) intra-articular adhesions and ankylosis, (2) all varieties of internal mechanical blocks, (3) active joint disease, (4) posterior capsular shrinkage, (5) extreme structural changes in the hamstrings, and (6) local conditions of the skin that prohibit the application of force.

It is unreservedly admitted that operative procedures have a definite field of indication in the treatment of kneejoint contractures. Tendon lengthening, stripping of the hamstrings from their point of origin, juxta-articular osteotomies, arthroplasty, alcohol injections of the peripheral nerves, resection of the joint, capsulotomy, capsuloplasty, and tendon transplantation are necessary in selected cases. Some of these procedures merely place the joint in a more favorable position for action.

A word of caution relative to open operative and closed manipulative (redressment force) methods, upon arthrogenic contractures especially, is imperative. Many of these patients are elderly and are poor operative risks because of the general pathological changes underlying the local cause of invalidism. The atrophic condition of the bones favors post-operative infection and fracture. Several such instances of infection with erosion of the popliteal vessels have been observed. Two cases of fat embolism resulted from the fractures incident to manual corrective attemps.

Autopsy examinations revealed extensive parenchymatous pathological changes, the occurence of which is too often overlooked in chronic arthritis. These cases combine all the optimum conditions for fat embolism in orthopaedic manipulations. The initial force drives the fat into the numerous vascular channels, because abundance of fat and vascularity are both characteristic of atrophic bone. In one case the fragility of the bones was dramatically demonstrated at autopsy, when the long bones were fractured with a minimum of effort. This complication is so insidious that it is often unsuspected until the symptoms of embolism make their grim appearance. Primary manipulation of arthritic joints has not been performed in this clinic for the past ten years.

The many mechanical appliances that have been devised for the gradual correction of flexion contractures of the knee are a tribute to conservatism. Those in use by Campbell, Smith, Lord, and others have much to recommend them, but usually require the construction of special apparatus. Their chief feature is directed against posterior subluxation already present, and its prevention during treatment. Juckelson states that the turnbuckle of Hackenbruch (Distraktionsklammer) was introduced in connection with the lower extremity in 1913. All joint contractures are treated by the turnbuckle method in this clinic wherever feasible. The elbow and the knee are by nature best adapted to this method.

The knee is situated in the center of two long levers with the joint as the axis of rotation. The turnbuckle-cast method depends upon the principle of three-point application of force. The principles of the second-class lever are utilized. It is absolutely essential that the joint remains the axis of motion of the system. The leg is considered to be the movable body. The moment of leverage is dependent upon the amount of force the angle of application, and its perpendicular distance from the center of rotation. The resistance to be overcome is the hamstring contracture as well as the weight of the leg. The possibility of initiating posterior subluxation (or increasing it, if it is already present) of the tibia must be considered in the practical application of this method.

If the force is applied distal to the insertion of the hamstrings and its resistance cannot be overcome, their point of insertion will become the center of rotation, with a resultant posterior dislocation of the upper end of the tibia.

When the resistance of the hamstrings is overcome, the center of rotation remains at the knee joint, and the leg rotates forward. The incorporation of hinges into the cast serves to maintain the center of motion at the joint. The correcting force resolves itself into a forward and a traction component. If a sliding type of hinge is used, the latter component may be utilized with advantage upon arthritic joints.

Mechanically, as correction proceeds, it becomes more difficult to overcome the resistance due to the decreasing angle of application. This contingency is met by placing the turnbuckles anteriorly, fixed to uprights incorporated in the cast. In this way a better purchase is obtained for the last few degrees of correction (Quengel method of Mommsen). Eccentrically placed turnbuckles easily overcome the external rotatory deformity before the hinges are included in the cast. By placing the hinges behind the center of motion of the knee, a forward thrust is exerted upon the upper border of the tibia, which tends to correct the subluxation.

The turnbuckle-cast method, in its several parts, is extremely simple. As a method of systematic procedure, attention to details is essential to obtain the best results.

The patella offers the counter-pressure to that which is applied posteriorly upon the thigh and leg. These areas require adequate protection. Special care is taken about the heel. A long leg cast is applied from the groin to the toes. Where considerable resistance is anticipated, a hip spica will serve to fix the thigh more firmly. A light, well-molded cast will favor weight-bearing early in the treatment. To minimize the resistance sometimes offered by the gastrocnemius, the foot may be fixed in equinus.

When the plaster has hardened sufficiently, it is divided all around the knee, leaving a tongue from the thigh portion snugly over the patella to insure a more even distribution of pressure over this area. In those cases where the subluxation and external rotation are negligible, the hinges and turnbuckles are incorporated into the two parts of the cast with the center of the hinges and the knee coinciding (center of the femoral condyles). Correction is exercised only within the tolerance of the patient, who in many instances soon learns to continue independently at home. Weight-bearing is encouraged just as soon as the plaster is hard enough, either with crutches, or in the gymnasium with the further aid of apparatus.

Retentive braces are worn for at least six months following correction to prevent recurrence of the contracture. In many cases the joints are insufficient to bear weight without support, because of the underlying joint pathology. An existing flexion contracture of the hip will be a factor in causing a recurrence, and must be corrected also. The same holds true for marked gastrocnemius weakness. In both situations locomotion induces a flexion position of the knee in order to satisfy gravital stresses. In some arthrogenic cases there remains a slight residual flexion deformity. This may be finally overcome by applying short skis to the shoes. This will allow the center of weight to be displaced forward, in the upright position, which will exert a correcting stretch upon the posterior structures of the knee.

There are those who offer the following objections to this method: decubitus ulcers, joint stiffness, atrophy, re activation of the joint pathology, and vascular and nervous disturbances.

Pressure complications can all be avoided by careful application of the cast. Immediate examination of the part causing complaint may prevent disappointment and alleviate suffering. It may be axiomatically stated that a definite decubitus is already present when the patient complains of actual pain. In our series these were rare and superficial.

Joint stiffness and some limitation of motion is usually primarily present in the arthrogenic type. The post corrective range of motion will depend upon the degree of joint destruction underlying the disability. Cast stiffness is minimized by having the patient execute the turnbuckle excursion daily. In the pure myostatic cases there should be no limitation of the joint motion, because the recovery of the normal length of the muscle fiber is effective and physiological by this method.

Muscular atrophy is also a usual accompaniment of arthrogenic contractures, and may be a factor in lessened resistance to correction. Daily active tension of the quadriceps and weight bearing do much to prevent progressive wasting. The duration of the cast period must be considered, and, in some instances, may be prolonged enough to warrant caution in this respect. The method of gradual correction gives the stretched extensors of the knee an opportunity to regain their normal tone. It has been observed that active insufficiency of the quadriceps has resulted from sudden correction, in several cases.

Reactivation of the joint pathology is seldom noted in properly selected cases. Its occurrence suggests that the joint was unsound at the outset of treatment. It is our custom to apply balanced traction to all cases exhibiting signs of activity, as a preliminary measure. Balanced traction will not in itself correct an actual contracture, but serves to overcome the muscle spasm due to some activity of the joint pathology.

Vascular and nervous disturbances were not observed in this series. Because there have been some definite reports of this in the literature, it is well to bear this possibility in mind. This complication should be feared much more in all the sudden corrective procedures. In those severe contractures that required operation it was never possible to obtain the full correction at once, due to the tension exhibited by the external popliteal nerve, which may also be taken as the index of the vascular tension. These were all finally corrected by the effective application of a turnbuckle cast.

CLINICAL DISCUSSION

Fifty-five cases have been treated by the turnbuckle-cast method, which includes fully seventy-seven knee contractures. There were twenty-three male and thirty-two female patients, in forty-six of whom the contractures were completely corrected. The average duration of the contracture was two and twenty-nine hundredths years, which is taken from the patients' statements, and must be considered with reservations; the actual time was in all probability less. The average time required to obtain full correction was thirteen and ninety-eight hundredths days. The average amount of contracture was thirty and forty-seven hundredths degrees. It is regrettable that the amount of deformity in the secondary planes was not recorded beyond a confirmation of their presence.

The arthrogenic group includes eighty per cent. of the total number. Twelve of these were over fifty years of age, and were in very poor general condition. Sixteen were total invalids at the beginning of treatment, and twenty exhibited multiple deformities. Most of them are now ambulatory, with or without some degree of mechanical support. In the great majority of those who had good motion before treatment, functional activity followed the removal of the casts.

Eight cases were not corrected. Three of these are still under treatment. Three had definite capsular shrinkage, one of which came to operation. This was a contracture of five years' duration incident to an osteomyelitis of the upper end of the tibia. The flexion was overcome from 100 degrees to 150 degrees after persistent turnbuckle correction. The posterior capsule was then stripped according to the technique of Wilson, and was found to be greatly thickened and even adherent to the posterior crucial ligament. Correction progressed to 165 degrees, the tension of the external popliteal nerve prohibiting further extension. When the wound was healed, a turnbuckle cast was effectively applied. It was then found that the old lesion had become reactivated, which necessitated drainage through an opening in a long leg cast, by the Orr method; this method maintained the corrected position. It is the opinion of the writer that the operative interference which necessitated exposure of the posterior part of the joint was the causal factor in the reactivation of the old osteomyelitic process.

An intercurrent infection interrupted the treatment in one case. In another a metastatic suppurative process, secondary to a boil on the neck, necessitated Orr drainage of the contracted joint. Thanks to this method of drainage, the amount of correction thus far obtained has not been lost, and a functional position of the knee has been retained.

In connection with the arthrogenic types of contracture, it may be stated that actual intra-articular adhesions are a rare occurrence. This has been impressed upon the writer by Dr. Steindler. Of the many knee joints that have been explored, relatively few have exhibited definite fibrous adhesions. This condition as a contra-indication to gradual correction has, therefore, been grossly overestimated.

Twelve of the earlier cases in the series were treated while some signs of joint activity were still present, with out complications other than moderate discomfort. There were seven superficial heel and patellar ulcers that responded readily to treatment. Active foci of infection must be taken care of. In one case the presence of an infected unguis incarnatis caused joint pain, which ceased after the local infection was removed surgically.

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TABLE 1

The arthrogenic contracture, clinically, increases its resistance as correction progresses. This is especially true in all types of contracture after actual shrinkage has occurred.

The opposite obtains for the hypertonic type of contractures. The initial resistance is the greatest, but when that is overcome, it soon yields to complete correction. The tendency to recurrence is inherent in the spastic contracture. Theoretically, because spastic contractures are labile, they may, under favorable conditions, be induced to reverse themselves. In the upper extremity the condition of “spasmus mobilis” is not uncommon, and has been observed in this clinic. Spastic extension contracture is rare in the lower extremity, but is always induced experimentally in the laboratory by the use of tetanus toxin. It is to the latter investigations that we owe most of our knowledge concerning contracture of muscles. Several hypertonic cases that have been corrected are being retained in extension in casts, in the hope that reversibility, in some degree, may be obtained. It should be remembered, in this connection, that while the genesis of contracture is dependent upon the higher centers and the integrity of the local reflex arc, it is entirely independent after actual contracture has taken place.

Congenital knee contracture can be corrected if attacked early. A case that could not be corrected by gradual extension is of particular interest. This boy presented bilateral marked spastic contractures incident to an extensive spina bifida occulta of the lower dorsal spine. Conservative treatment begun about ten years after birth was ineffective. The child had never walked, and both knees were in 140 degrees of extension at the time of operation. A posterior capsuloplasty, combined with tenotomy and lengthening of the tensor fasciae femoris and all the ham- strings, resulted in 160 degrees of extension. Here again the turnbuckle cast was effective in completely correcting the remaining deformity in about three weeks.

The postural and the paralytic types may be considered together. The results of treatment by gradual correction were excellent. Due to the unopposed action of the tensor fasciae femoris, which so frequently escapes paralysis, the paralytic type of knee contracture is usually remarkable for the degree of valgus and external rotation, which, in extreme cases, may require additional osteotomy. In this group it is especially important to correct all associated deformities and deficiencies, in order to prevent recurrence. The presence of strong glutei and gastrocnemius will exert an extensor thrust upon the knee during locomotion. In recumbency the latter may favor flexion and recurrence.

CONCLUSIONS

Flexion contracture of the knee follows definite physical laws, which apply to all muscular contractures, and is modified by its peculiar anatomical construction.

Gradual correction by the turnbuckle-cast method is offered as the method of choice, in the great majority of cases, because it has proved to be actually effective in a series of cases, including seventy-seven flexion contractures of the knee joint treated in this clinic. It provides a rigid system, which is so essential for the application of a correcting force upon the largest joint in the body. It may be universally applied, and does not require the construction of special apparatus. It is a method that is urged as a primary procedure, but its further utility preliminary or secondary to operative measures should not be overlooked. Its early application is especially indicated in con tractures following actual involvement of the joint, before capsular shrinkage has occurred. As a preventive means, turnbuckles may be incorporated into every cast applied upon a pathologically flexed knee, in order to encourage correction just as soon as activity subsides. In this way even cases of tuberculosis of the knee may be given a better functional position.

The writer wishes to express his appreciation of Dr. Steindler's enthusiastic encouragement, valuable guidance, and his correction of the manuscript.

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Parker, C. A.: Treatment of Pathologically Flexed Knee. J. Am. Med. Assn., LXXXI, 1198, 1923.

*From the Department of Orthopaedic Surgery, the State University of Iowa, Service of Dr. Arthur Steindler.

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