[Tridimensional gait analysis after unilateral subtalar arthrodesis]

PURPOSE OF THE STUDY

Subtalar arthrodesis can be useful in various conditions. Initially used for the treatment of congenital or acquired foot deformities, it was later applied to surgical repair of traumatic injury. The subtalar joint does however play an important role in gait, particularly for transmitting rotational movement of the leg to the foot. The functional outcome after subtalar arthrodesis has been the object of many studies. These studies examined clinical and radiological results and raised the problem of determining the appropriate extent of the fusion. None of these studies has however provided a three-dimensional analysis of gait after subtalar arthrodesis, performed in the present work.

MATERIAL AND METHODS

We used the Vicon VX3D system with 2 integrated force platforms. Acquisition was made at 50 Hz. The Vicon recording was coupled with EMG recordings of the gastrocnemius, the rectus, the anterior tibialis, and the glutius medius. Gait was analyzed in 8 patients who had undergone unilateral subtalar arthrodesis at least 18 months earlier. Several recordings were made for each patient but only one complete gait cycle was retained for analysis of kinematic, kinetic and electromyographic curves and ground reaction forces. Wilcoxon's test for paired series was used to compare the operated side to the healthy side (excepting EMG recordings).

RESULTS

The operated and healthy side were significantly different. Total amplitude of joint movement was lower for the operated side: 16.5 degrees versus 21.5 degrees for the healthy side. Peak power generated at the ankle for plantar flexion was lower at the end of the stance phase. Electromyography recordings showed a shift in muscle activity between the healthy and fused foot.

DISCUSSION

Few statistical differences were found between the tested values. It can thus be concluded that gait pattern is globally symmetrical after subtalar arthrodesis and that this fusion has little functional impact on the knee or the hip. The difference in amplitude between the healthy and operated side showed a wider variability than observed by Winter in the healthy subject that was also greater than the measurement error reported by Laasel. We did not perform a statistical analysis of the EMG data since the values recorded were arbitrary and the observed shift in activities had no general impact.

CONCLUSION

Despite the reduction in flexion-extension amplitude of the ankle, subtalar arthrodesis allows a globally symmetrical gait in the experimental conditions described.

Long-term efficacy of percutaneous drill-biopsy under computed tomography guidance of osteoid osteomas of the hip and femur. A review of seven cases

En bloc surgical excision of osteoid osteomas of the hip and femur is difficult because of problems with tumor boundary identification and the need to use internal fixation or bone grafting. We report our experience with seven cases treated by percutaneous drill-biopsy under computed tomography guidance.

PATIENTS

Six adults and one child with a mean age of 22 years treated since 1995. All seven patients reported insomnia due to pain during a mean of 10 months, improved by aspirin or other nonsteroidal anti-inflammatory agents. The tumor was seen on plain radiographs in four cases and on computed tomography scans in all seven cases. Magnetic resonance imaging was diagnostic in only two cases. The tumor was in the femoral neck in four patients, in the acetabulum in one, in the proximal femur in one, and at the distal diaphyseal-metaphyseal junction of the femur in one.

METHOD

A trephine was used to remove the tumor under computed tomography guidance during a short general anesthesia.

RESULTS

No serious complications were recorded. Full weight bearing was allowed starting at the forty-eighth hour in six of the seven patients. Immediate pain relief and a full recovery were obtained in every case. Results were excellent in four patients and good in three after a follow-up of 14 to 44 months.

CONCLUSION

Percutaneous drill-biopsy of osteoid osteomas is a valuable alternative to conventional surgery in patients with tumors at sites that are difficult to access. The technique allows early weight bearing and ensures a full recovery.

[Bankart procedure: clinical and radiological long-term outcome]

PURPOSE OF THE STUDY

There are few reports onlong-term outcome after Bankart procedure. The purpose of this study was to determine the rate of recurrent dislocation, the clinical results and the incidence of glenohumeral osteoarthritis after a minimum 10-year follow-up.

MATERIAL AND METHODS

Ninety-seven Bankart procedures were performed in 97 patients between 1972 and 1986 for treatment of anterior shoulder instability with recurrent dislocations. We retrospectively reviewed 74 patients and obtained 64 complete radioclinical evaluations for an average follow-up of 16 years. Clinical evaluation was based on the G. Walch and the Duplay group score but for easier comparisons, we also calculated the Rowe et al. score. Radiographical evaluation was established on the Samilson and Prieto classification but real glenohumeral osteoarthritis with joint narrowing was noted independently as grade four. We also studied the contralateral shoulder.

RESULTS

At last follow-up, 7 shoulders (9.5%) had recurrent dislocation, but two of them occurred subsequent to severe trauma over 18 months. Most patients (95 %) were satisfied or very satisfied. Six patients (8.1%) had persistent apprehension but in some it was not due to anterior apprehension. According to the Duplay score (or the Rowe score), 25 shoulders (44.6%) had an excellent result (35/61.4 %) 16 (28.6%) a good result (7/12.3%), 11 (19.7%) a fair result (11.19.3) and 4 (5.4 %) a poor result (4/7%). Operated shoulders were pain free for 75% and painful for forced movements only for 25%. External rotation at 90 degrees of abduction was reduced by 8.7 +/- 15.7 degrees. There was no limitation of internal rotation. Patients returned to preoperative sports activities at the same level for 70.9 % and at a lower level for 12.7%. According to the Samilson classification, 7 (13%) of the shoulders had grade 2 and 2 (3.7%) had grade 3 glenohumeral osteoarthritis. We found 4 cases (7.4%) of real glenohumeral osteoarthritis (grade four) and 2 of these patients had contralateral osteoarthritis of a non unstable shoulder. There was no perioperative complication.

DISCUSSION

In our hands the Bankart procedure is appeared as a safe procedure with a low rate of glenohumeral osteoarthritis and a high rate of patient satisfaction.

[In vivo study of kinematics of the elbow using electromagnetic goniometer]

We used an electromagnetic goniometer to study the angular and translations displacements between the humerus and the 2 bones of the forearm. The electromagnetic gionometer allows acquisition of the coordinates and analysis of the 6 degrees of motion. To validate our external fixation apparatus, we used a fresh body upper limb. At first, a series of measurements was conducted with the apparatus. We then performed a series of measurements, by fixing the transmitter and receiver with external fixation pins directly inserted into the bones of the arm and forearm. To assess the reproducibility of our method, we chose a healthy subject. We performed 20 measurements over his right and left elbows. In order to study normal elbow kinematics, we performed measurements on 10 healthy subjects. The study of rotation showed that the apparatus was adapted to measure flexion-extension. It limited pronation-supination movement to about 26.7 degrees. Abduction was increased by 19.7 degrees by our apparatus during flexion-extension, but abduction was reliable within a 2 degrees range for pronation-supination. The sliding movements recorded during flexion-extension were reliable within approximately 3 mm for frontal translations, 6 mm for fitting, and 1 mm for external translations. For the sliding movements recorded in pronation-supination, frontal translations were reliable within about 7 mm, fitting was reliable within 1.9 mm and external translations were reliable within about 2.9 mm. During flexion-extension of the elbow, flexion-extension, frontal translations and external translations were reproducible. The reproducibility test showed that only 6 measurements were reproducible. The kinematic elbow study of a healthy subject showed that the average amplitude of flexion-extension was close to the measurement observed with the manual goniometer. The results in the healthy subject showed that the elbow is more stable during pronation-supination than during flexion-extension. This preliminary study should allow us, in the near future, to study elbow prosthesis kinematics.

A trans STT, trans capitate perilunate dislocation of the carpus. A case report

We report a case of carpal injury not previously described, associating three lesions of the carpus secondary to a hyperextension mechanism: fracture of the capitate, scapho-trapezio-trapezoid sprain and lunotriquetral ligament rupture. The patient was operated by percutaneous pinning after closed reduction. The capitate fracture was not fixed. At follow-up, the patient had no restriction of his everyday activities and was very satisfied.

[Radiographic course of 39 rheumatoid wrists after synovectomy and stabilization]

Between 1984 and 1995, 39 patients underwent wrist synovectomy-stabilisation. Among these patients, 5 had died and 2 could not rectum for review. These 7 patients were excluded from the study. 32 patients were therefore included in the study. These patients had an average age of 50 years, with an average follow-up of 65 months. We used the Larsen classification to assess wrist osteo-articular involvement. To evaluate carpal instability, we measured: the carpal height with the Mac Murtry index, Shapiro's angle and the modified Shapiro's angle (the angle between the radial diaphysis and the second metacarpal diaphysis), the angle of finger ulnar deviation, the carpal ulnar deviation with the ulnar deviation index of the carpus, the radial deviation with the radial deviation index of the carpus, the carpal frontal dislocation. Carpitis continued to develop and Larsen's grade deteriorated in 50% wrists despite surgery. The average value of the radial sliding index of the carpus increased from 0.11 to 0.15: this showed an average ulnar sliding of 2.2 mm. The average Shapiro's angle increased from 118.2 degrees to 125 degrees. At follow-up, we observed anterior translation of the carpal bones and an increased distance between the proximal and distal carpal rows. The distance between the proximal and distal rows of the carpus appeared to be corrected by extensive synovectomy. Radio-carpal and mid-carpal synovectomy increased the carpal ulnar sliding. The modified Shapiro's angle was corrected by transfer of the extensor carpi radialis longus onto the extensor carpi radialis brevis. In contrast with other operations without stabilisation, the Sauvé-Kapandji procedure limited ulnar sliding and radial tilting of the carpus. Stabilisation of the carpus therefore participates in control of ulnar deviation of the long fingers. Transfer of the extensor carpi radialis longus onto the extensor carpi radialis brevis seems effective on wrist relaxation, by medialization of the traction force of the extensor carpi radialis longus. Our results with of Larsen stage IV were encouraging. The indication for wrist arthrodesis could be limited to stage IV with radio-carpal dislocation or stage V.

Effect of the Steindler procedure on the median nerve branches to the medial epicondylar muscles

Usually the median nerve gives off six branches to the muscles arising from the medial epicondyle, which could be tightened during Steindler's procedure. We studied these branches before and after Steindler's procedure in 20 fresh cadavers and observed a considerable variation in the origin of the branches. The muscular branches arising from the median nerve did not seem to limit the mobilization of the medial epicondyle when performing Steindler's transfer. The limitation of the flexion observed after Steindler's procedure was mainly related to the tension of the transferred forearm flexor muscles. The variability of the origin of the branch to the flexor digitorum superficialis muscle could explain a lesion of this branch when Steindler's procedure is carried out with Brunelli's modification. The lateral transfer and the anterior transfer on to the humeral shaft did not influence the limitation of elbow flexion or result in tightness in any nerve branch to the transferred muscles.

Comparison of two modes of administration of a personalized quality of life scale in a longitudinal study of total hip arthroplasty

Quality of life scales are being increasingly used to evaluate patients. The earliest scales were standardized questionnaire that did not necessarily provide an optimal evaluation of the quality of life of each individual patient. A number of personalized scales are now available, including the SEIQoL, in which the patients nominate the five quality of life areas most important to them. The SEIQoL has been validated. We tested the SEIQoL in patients treated by total hip arthroplasty, a procedure that is expected to improve quality of life.

OBJECTIVE

To compare two methods of administration of the SEIQoL several months after total hip arthroplasty.

METHODS

The SEIQoL was administered before and after the arthroplasty. During the postoperative test session, the SEIQoL was administered twice, once using the items nominated preoperatively and once after allowing the patient to repeat the nomination procedure.

RESULTS

With both methods, significant improvements in quality of life were demonstrated (P < 0.05). There was no significant difference between the two methods.

CONCLUSION

Changing the items of the SEIQoL during prospective studies does not modify the overall quality of life score. Keeping the same items throughout the study is nevertheless warranted.

[Laxity and functional results of Miller-Galante total knee prosthesis with posterior cruciate ligament sparing after a 6-year follow-up]

PURPOSE OF THE STUDY

The preservation of the posterior cruciate ligament (PCL) was introduced in total knee arthroplasty to improve the quadriceps efficiency and the range of flexion in stairs. The purpose of this study was to determine if these goals were achieved with the Miller-Galante total knee prothesis and to assess the relation between knee laxity and function.

MATERIALS AND METHOD

We assessed retrospectively the results of 48 consecutive Miller-Galante with PCL retaining. Four patients were excluded: 2 died, 2 lost to follow-up. Forty-four prostheses were evaluated in 38 patients mean aged 65 (33-79). The preoperative HSS score was 41 +/- 12.4 [21-63]. All the components were cemented with patellar resurfacing (25 metal-backed, 19 polyethylene). Stressed X-rays with Telos device were performed to assess frontal and antero-posterior laxity. All radiographic measurements were carried out with a digitizer (Orthographics).

RESULTS

After 6 years of follow-up, 8 prostheses (18.1 p. 100) were already revised because of: 1) 3 excessive anterior tibial translations and severe polyethylene wear; 2) 5 femoro-patellar disorders. These last 5 knees (4 patellar metal-backed) had a greater patellar thickness [(25 mm +/- 1.2) (p = 0.01)]. The mean HSS knee score for the 36 remaining prostheses was 73.8 +/- 11.3 (35-92). Only 5 patients were able to climb stairs without support. The mean mechanical axis was 2.3 degrees in varus, but 81 percent of the knees were at 5 degrees around neutral position. The mean laxity in valgus was 4 degrees +/- 2.3 degrees [1-10], and 4.1 degrees +/- 2.1 degrees [1-9] in varus. The mean anterior tibial translation was 5.3 mm +/- 5 [1-17] and posterior laxity was 4.7 mm +/- 2.5 [1-10]. HSS knee score was lowered by 9 points when frontal laxity (valgus + varus) was greater than 5 degrees (p = 0.01), and by 9.8 points when posterior laxity was 5 mm or more (p = 0.02). The mean thickness of the patella was 22 mm +/- 2.3 [16-27].

DISCUSSION

These results were unsatisfactory considering the high revision rate and the low functional score observed despite of a correct implant positioning. The major challenge for PCL retaining (i.e. free stair climbing) was achieved in few cases. The wide range of posterior laxity underlined the difficulties to control PCL tension. On the other hand, PCL tension has to be controlled as it could influence knee function. Patello-femoral disorders was the main reason for revision surgery and an insufficient patellar bone resection may be contributive. Sagittal anterior laxity was the second reason for revision and it should be carefully detected as it could drive to catastrophic polyethylene wear.

CONCLUSION

The advantages of PCL retaining were not demonstrated with this low constrained design. Surgical control of PCL tension could give a wide range of posterior laxity. Sagittal femoral-tibial laxity and femoro-patellar disorders should be detected before severe polyethylene wear. These results advocates for: 1) more congruent designs with PCL retaining or for PCL substituting designs, 2) improvement of patello-femoral design.

[Retrospective study of 23 arthrolyses of the elbow for post-traumatic stiffness: result predicting factors]

INTRODUCTION

The goal of the study was to determine the results of elbow arthrolysis for post-traumatic stiffness, and to identify factors governing the result of that procedure.

PATIENTS AND METHODS

Between 1984 and 1997, 26 elbow arthrolysis were performed. Twenty-three patients were retrospectively assessed by an independent examiner, 3 patients were lost for follow-up. The mean age at surgery was 41 years. The traumatisms responsible for stiffness were: 5 elbow dislocations, 7 radial head fractures, 3 olecranon fractures, 8 humeral palette fractures. The surgical approach was 2 times posterior, 9 times lateral, 12 times combined (posterior and lateral). The surgical approach was chosen according to the preoperative analysis of the stiffness factors and the scars in case of previous surgery.

RESULTS

At follow-up (85 months (12-144)), 5 patients were very satisfied, 17 patients were satisfied and one patient was not satisfied. Six patients had discomfort in daily gesture. Ten patients had no pain, 6 had pain while effort and 7 had climatic pain. Two ulnar palsies existing at arthrolysis did not improve after neurolysis and anterior ulnar nerve transposition. Range of motion increased in every sector of mobility, and at follow-up mean ROM was: 121 degrees flexion, -31 degrees extension, 69 degrees pronation and 65 degrees supination. The average absolute benefit in flexion-extension was about 38 degrees. The average relative (flexion-extension) benefit according to Merle d'Aubigné was about 44%. At follow-up, the average pronation-supination was higher than 100 degrees. The range of motion was not correlated to the type of injury, to the surgical management, nor to the type of rehabilitation program. Likewise, the delay between traumatism and arthrolysis had no influence on the result. On the other hand, the range of motion was directly correlated to the preoperative mobility and mobility obtained just after surgery (p = 0.001). However, the range of motion at follow-up was slightly decreased (5 degrees to 15 degrees) compared to the mobility obtained just after surgery.

DISCUSSION

The final range of motion was mainly related to the severity of the preoperative stiffness. We noticed that few patients were bothered in daily gestures, in spite of a relative stiffness. The type of injury did not seem to influence the final result. Elbow arthrolysis remains a mobilizing technique giving reliable long-lasting results.

CONCLUSION

The range of motion obtained after arthrolysis performed because of elbow post-traumatic contracture is mainly related to preoperative stiffness. By comparing with postoperative range of motion, a loss of 5 degrees to 10 degrees can be predicted.

[Reliability of the KT-1000 arthrometer in measuring anterior laxity of the knee: comparative analysis with Telos of 48 reconstructions of the anterior cruciate ligament and intra- and interobserver reproducibility]

PURPOSE OF THE STUDY

The goal of this study was to compare KT-1000 and Telos measurements after anterior cruciate ligament reconstruction (ACLR).

MATERIAL AND METHOD

Forty eight patients with asymptomatic ACLR (4 failures with positive pivot shift and 12 knees with positive (+) Lachman test) were assessed (mean 2.5 years after surgery) by the same examiner by means of: 1) Lachman radiographic with Telos at 150 N, 2) MEDmetric KT-1000 at 69 N, 89 N and maxi-manuel (MM). The examiner tested more than 200 patients each year. Measurements were performed for KT-1000 according to the manufacturers' recommendations and for Telos according to Staübli. Only side to side differences in millimeters are reported. Reproducibility of KT-1000 measurements were also evaluated: interobserver reproducibility was assessed by 16 examiners on a healthy patient, and the experienced examiner tested 20 times a healthy patient.

RESULTS

An Interobserver error of 4 mm range (+/- 2 mm related to 0) was observed by 12 to 44 p. 100 of the examiners, respectively at 69 N to MM. An intraobserver error of 4 mm range (+/- 2 mm related to 0) was observed in 10 p. 100 at MM and in 20 p. 100 at 89 N. Mean side to side laxity with KT-1000 was 0.93 mm +/- 1.1 [-1 to 5] at 69 N, 1.3 mm +/- 1.6 [-2 to 6] at 89 N, and 1.41 +/- 1.8 [-2 to 6] at MM. With Telos the mean side to side laxity was 3.95 mm +/- 3.84 [0 to 15]. Significant differences (p = 0.0001) were found between measurements obtained by the two methods. No statistical correlation could be detected between values observed by Telos and KT-1000 (R < 0.1). If we consider a 3 mm side to side difference 23 knees (48 p. 100) had abnormal anterior laxity with Telos and with KT-1000 only 3 (6.2 p. 100) at 89 N and 6 (12.5 p. 100) at MM (1 (2 p. 100) at 69 N). With a 5 mm side to side difference, 12 knees (25 p. 100) had abnormal anterior laxity with Telos and with KT-1000 only 1 (2 p. 100) at 89 N and 1 (2 p. 100) at MM (0 at 69 N). Only Telos measurements were correlated to positive pivot shift (p = 0.007) and positive Lachman test (p = 0.01).

CONCLUSION

Interobserver reproducibility of KT-1000 measurements was low, but improved for intraobserver agreement. However, even for a unique KT-1000 experienced examiner, reliability of KT-1000 was poor when comparing Telos and KT-1000 predicitive value to diagnose ACLR failure. Telos results were much more pejorative but the only ones corelated with ACLR failures. We recommand Telos instead of KT-1000 to assess laxity after ACLR.

Synovectomy combined with the Sauvé-Kapandji procedure for the rheumatoid wrist

The aim of synovectomy-stabilization (synovectomy combined with the Sauvé-Kapandji procedure) of the rheumatoid wrist is to obtain a stable painless wrist, retaining enough mobility for function. Thirty-nine wrists were retrospectively examined, at a mean follow up of 64.8 months. The improvement in pain was very significant. We noticed a decrease in wrist motion affecting both flexion and radial deviation. The arthritic change in the wrist continued to increase. We noticed a mean ulnar shift of 2.2 mm and a mean increase in the radial deviation of the wrist of 7 degrees. Only transfer of the extensor carpi radialis longus tendon to the extensor carpi radialis brevis tendon was effective in correcting radial deviation of the carpus. Ninety-seven per cent of patients were very satisfied or satisfied. These encouraging results, even at advanced stages of wrist arthritis, have prompted us to lessen the indications for wrist arthrodesis.

[Reproducibility of the radiographic analysis of dysplasia of the femoral trochlea. Intra- and interobserver analysis of 68 knees]

PURPOSE OF THE STUDY

The relation between patello-femoral instability and trochlear dysplasia was identified by Dejour. Trochlear dysplasia, diagnosed on knee lateral Xray when the trochlear groove crosses both femoral condyles (the so-called "crossing sign"), must be corrected to improve patello-femoral stability. However surgery should be related to the severity and the shape of trochlear dysplasia, underlining the importance of a reproducible classification. The aim of this study was to establish intra and inter-observer reliability of Dejour's radiographic criteria.

MATERIAL

68 preoperative exact knee profile radiographs were harvested from clinical records of 64 patients who underwent trochleoplasty because of patello-femoral instability and trochlear dysplasia. On these 68 views, the crossing sign was identified by the senior surgeon (F.G.) who performed or supervised surgery.

METHOD

The 68 radiographs were examined independently by 7 observers (2 juniors, 5 seniors) in order to assess interobserver agreement. Two juniors repeated the observation to test intraobserver agreement. Reproducibility for categorical data (7 shapes of trochlea according to Dejour (3 for dysplasia)) was evaluated by Kappa statistics, and for numerical data (depth and anterior projection of the trochlear groove with respect to anterior femoral cortex) we used the interclass correlation analysis.

RESULTS

Two out of the 7 observers rated all the 68 trochleas as dysplastics. The 5 others rated as normal 1 to 6 trochleas out of the 68. None of the 68 trochleas were recognized with the same shape by the 7 examiners. At best, 6 observers agreed on the same shape and for only 12 trochleas. Disagreement was mostly related to mistakes between type I and type II of dysplasia. For trochlear morphology interobserver agreement was slight (Kappa = 0.17) and intraobserver agreement was fair (Kappa = 0.3). The mean prominence of the trochlea was 3 +/- 2.1 mm [-6 to 10], and the mean trochlea depth was 1 +/- 1.9 mm [0 to 11]. These measurements were more reliable since the interclass correlation coefficients were respectively 0.62 and 0.38. The level of experience of the observers had no influence for categorical or numerical data.

DISCUSSION

Our results indicated a low interobserver agreement for trochlear shape identification according to Dejour. The most reliable criteria was measurement of the trochlear prominence which was mostly pathological in our series. The "crossing sign" was reliable to diagnose dysplasia since the probability to rate as normal a true dysplastic trochlea was only 3.1 per cent. However, once the dysplasia diagnosed, this classification gave inconsistent results to select the trochlear shape, particularly for type II. To improve reproducibility we propose to diagnose a type II only when 5 millimeters separate the crossings between the medial and lateral condyles.

CONCLUSION

We recommend to use anterior projection of the trochlear groove to rate trochlear dysplasia and to determine the adequate type of trochleoplasty: elevating of the lateral facet if non prominent or deepening of the groove when prominent.

Inter- and intraobserver reproducibility in radiographic diagnosis and classification of femoral trochlear dysplasia

Dejour's radiographic criteria are commonly used to diagnose and assess femoral trochlear dysplasia in case of patello-femoral instability. The aim of this study was to establish the intra- and interobserver reliability of these radiographic criteria. Sixty-eight lateral knee radiographs were examined independently by 7 observers (2 juniors, 5 seniors) to assess interobserver agreement, and the 2 juniors repeated the observations to test intraobserver agreement. These 68 true lateral views were harvested from clinical records of 64 patients who underwent a trochleoplasty because of patellofemoral instability. To evaluate the agreement on analytic data (morphologic type of trochlea) we used the kappa statistical method, and to evaluate the agreement on numerical data (depth and prominence of the trochlear groove) we used interclass correlation analysis. The "crossing sign" (between the trochlear groove and the anterior aspect of both condyles) was reliable since the probability of rating as normal a pathologic trochlea was only 3.1% (0 to 8.8%). In classifying trochlear morphology interobserver agreement was slight (kappa = 0.17) and intraobserver agreement was fair (kappa = 0.3). On the other hand, the measurements of the depth and prominence of the trochlear groove were more reliable since the interclass coefficients between observers were 0.62 and 0.38 respectively. The most frequent interobserver error was related to misdiagnosis of type II. To clarify Dejour's criteria we propose a diagnosis of type II only when 5 mm or more are measured between the intersections with the medial and lateral femoral condyles. We recommend the use of the prominence of the trochlear groove to evaluate the grade of bony trochlear dysplasia.

[Femoral reconstruction with endosteal bone allografts protected by a metallic mesh in reoperation of total hip prosthesis. 19 cases with an average follow-up of 83 months]

PURPOSE OF THE STUDY

To assess after 83 months of follow-up, the results of 19 femoral revisions carried out according to an original method combining a cemented stem and bone reconstruction by means of impacted-morcelized bone allograft protected by a titanium mesh.

MATERIALS

Twenty hips (18 patients mean aged 58 at surgery) were included between 1986 and 1991. Five hips had a least one previous prosthetic revision, one hip was revised because of septic loosening. No patient was lost for follow-up, but two had died during the follow-up period: one patient died one month after surgery was excluded, one other died 7 years after the index procedure and was included with his last hip rating. Loss of femoral bone stock was severe according to the SOFCOT four stage rating system: 2 femurs were grade II, 14 grade III, and 3 grade IV. Femoral stem migration was assessed with landmarks recommended by Walker. All the measurements were performed with a digitizer (OrthoGraphics).

METHODS

All the procedures were carried out through a posterolateral approach, augmented by 4 trochanteric osteotomies and 5 distal femoral windows. After prosthesis and cement removal, a bone plug was placed into the medullary canal. Then, cancelous bone morcelized allografts were impacted in the femoral defects through the medullary canal. A titanium mesh cylinder was placed into the femur to separate the graft from the cement introduced later to obtain fixation of the revision stem. The stem was extended about 5 centimeters over the distal edge of the grafts in order to bridge the femoral defects. The mesh was extended only in front of the grafts and was used to protect them from excessive cement penetration.

RESULTS

Functional improvement was noticeable since the Merle d'Aubigné Hip score improved from 9.8 to 16.3 at follow-up. The pain score improved from 2.1 to 5.5 and walking score from 2.3 to 5. Adverse effects occurred during the first cases and were related to cement removal: 3 greater trochanter fractures, 5 distal femoral perforations and 2 non displaced femoral shaft fractures. The septic revision had recurrence of infection associated with radiolucent lines > 2 millimeters and the only one graft resorption. One trochanteric non-union was observed but no prosthetic dislocation. Only one femoral stem migration (4.4 millimeters) was detected without any other radiographic features of loosening after 9 years of follow-up. This stem was considered as loosed, but was not revised because of few clinical symptoms. Only 2 radiolucent lines less than 2 millimeters at the bone cement interface in Gruen's zones 3 to 5. Likewise, no radiographic feature of stress-shielding was observed. On follow-up X-rays, 3 hips had corticalisation of the grafts, and 12 hips demonstrated normal cancelous trabeculations in the grafts.

CONCLUSION

Satisfactory functional and radiographic results were obtained with this method after 5 to 10 years of follow-up instead of severe preoperative femoral bone stock impairement. Likewise, we observed only one recurrence of loosening diagnosed with the help of digitized X-ray examination. Only one significant (> 3.5 mm) femoral stem migration was detected. Radiographic features of femoral reconstruction were observed but without histologic proof of graft integration. This method uses a longer stem than the "Exeter", but avoids a high rate of femoral stem migration and appears compatible with femoral bone reconstruction.

[Temporary antibiotic-loaded cemented prosthesis for two-stage septic hip arthroplasty]

PURPOSE OF THE STUDY

During the excision period of a two-stage revision arthroplasty, the hip has a low function and an unacceptable leg length discrepancy. The goal of this study was to expose technical details in order to perform a simple articulated cement spacer which could be implanted during this period to improve hip function, to authorize partial weight bearing and to avoid leg length discrepancy.

MATERIAL

This method was applied in three two-stage procedures justified because of particular immunodeficiency conditions: a 43 years old man who had bone marrow allograft and immunosuppressive therapy because of leukemia suffering of subacute septic hip arthritis; a 58 years old man suffering of diabetes and active C-hepatitis who had a septic loosening of a total hip arthroplasty (THA); a 76 years old woman suffering of diabetes who had a third septic loosening of THA.

METHOD

The prosthesis was made of antibiotic-impregnated cement according to organisms antibiotic resistance. The prosthetic junction between head and diaphysis was reinforced with a tibial plate. Prosthetic shape was identical to the one of femoral broaches inserted in the femur after prosthetic and cement removal. The broach size was chosen when mechanical stability in the femur was obtained, and avoided leg length discrepancy after trials with cups. The tibial plate was bent in order to reinforce the junction with regard to the shape of the determined broach. Two doses of antibiotic-impregnated cement were mixed and molded with hands, then the plate was incorporated at the appropriate location, finally the broach was applied on this composite and cement in excess was removed before polymerisation. For prosthetic head, two options were available: to mold the cephalic zone of the cement at the patient acetabulum diameter with a soft aluminium cup previously molded in the acetabulum; to mold the cement cephalic zone with a trial cup in order to obtain a 22 or 28 ball. For this last option, a third dose of antibiotic-impregnated cement was prepared and placed in the acetabulum, a trial femoral head was applied in it to mold the location for the 22 or 28 prosthetic head. Before insertion, a collar was applied on the stem to prevent migration. Active mobilization was encouraged, and partial weight-bearing authorized.

RESULTS

The mean range of hip flexion during period was 60 degrees. The patients were discharged approximatively 12 days after the first stage. Two patients had effective painless partial weight-bearing. The second stage was performed six weeks later on the average. The second procedure was easier than the second stage of a conventional two-stage procedure because of: easy and low hemorrhagic dissection authorized by the prosthesis; low difficulties with soft tissue tension as the prosthesis prevents leg length discrepancy; preservation of the articular space which prevents soft tissue sacrifice during the second stage.

CONCLUSION

This simple technique is effective to prevent complications related to the excision period of a two-stage hip revision arthroplasty. Likewise, the economical aspect (short delay of hospitalisation, quick functional recovery) should be considered when compared with the excision period of a conventional two-stage procedure.

[Arthrodesis of the wrist in inflammatory arthropathy. Effects of fusion of intracarpal joint spaces on functional results]

We retrospectively analysed 25 wrist arthrodeses performed in 23 patients because of inflammatory joint disease (21 rheumatoid arthritis, 1 case of Still's disease, 1 case of psoriatic arthritis) to assess: 1) the functional result, the position and the fusion rate; 2) the correlation between the radiographic features and the results on pain. The results were evaluated after an average of 56 months (12-121) by an observer not involved in surgery. 8 wrists were pain-free, 12 caused occasional pain, 4 caused frequent pain and 1 wrist was responsible for continuous pain at follow-up. The position of the arthrodesis was acceptable in the sagittal plane (mean extension 4.3 degrees), but with a slight ulnar tilt (mean ulnar tilt 12.8 degrees). Fusion was achieved in all cases after a mean of 8.2 weeks (5-16). All the intracarpal joints had united in only 8 cases, while the scaphotrapezo-trapezoid joint had not united in 17 cases, but fusion was spontaneously obtained in 8 cases. We identified 5 non-unions between lunatum and triquetrum, 5 non-unions between hamatum and capitatum and 3 non-unions between triquetrum and hamatum. Pain at follow-up was related to non-union of triquetro-lunate joints (p = 0.035). Wrist arthrodesis remains appropriate for severe lesions of the rheumatoid wrist in order to restore function and relieve pain.

[Value of a synthetic osseous model obtained by stereo-lithography for preoperative planning. Correction of a complex femoral deformity caused by fibrous dysplasia]

PURPOSE OF THE STUDY

The authors investigated the application of life-sized bone models obtained by stereolithography in orthopaedics.

MATERIALS

The method was applied to planify correction of a severe femoral bone deformity secondary to fibrous dysplasia in a 27 years old man. This deformity was responsible for abnormal hip range of motion 70 degrees/-10 degrees (flexion-extension), -20 degrees/60 degrees (abduction-adduction), -30 degrees/60 degrees (external-internal rotation), and restricted walking ability because of lack of abduction and external rotation. A "shepherd-cross" deformity was identified on X-rays. A correction osteotomy was considered but we were unable to planify the angle of osteotomy on plain X-rays. CT scan identified 100 degrees of varus cervical deformity and 90 degrees of cervical antetorsion, but CT scan was helpless to choose the position for the osteosynthesis device.

METHODS

2D pictures obtained by CT scan were introduced and treated on a Silicon Graphics Indigo2 hardware. Mimics software authorized 2D and 3D views of bone which were separated of soft tissue by color separation process. CTM software authorized the 3D bone surface reconstruction (3D files). The 3D files were used to obtain life-sized bone model in 6 hours by stereolithographic process (scale 1/1).

RESULTS

We planified a 70 degrees valgus and 40 degrees derotation and chose the best location for osteosynthesis device considering the fibrous dysplasia (best location was the posterior and superior aspect of the femoral neck). The planified osteotomy was performed and we obtained the stability of a nail-plate in the femoral neck. During surgery, we observed the bone model and the deformed femur had the same shape. Likewise, the model strongly indicated the inside bone structure (ie distribution of fibrous dysplasia tissue). Bone healing was obtained after 5 months with improvement of range of motion [(70/0) (20/30) (30/20)]. Histologic examination diagnosed fibrous dysplasia without malignancy features.

CONCLUSION

Computer-generated life-sized bone models are available from computer tomographic data by means of stereolithographic process. This technic was helpful to improve planification of this complex proximal femoral osteotomy. Obtaining life-sized bone models could improve preoperative planning in case of multidirectional deformity, unusual site for osteotomy, or severe deformity impairing the choice for fixation device or its position into bone extremities. The indications for this method should be restricted to unusual and severe bone deformities, with inadequate preoperative assessment by standard X-rays or CT scans. Likewise, this method could be indicated for preoperative planning of technically demanding osteotomies such as oblique plane.

[Complete elbow prosthesis for inflammatory and hemophiliac arthropathy. A retrospective analysis of 22 cases]

We retrospectively analysed 22 total elbow prostheses (8 GSB III, 14 Kudo) implanted because of inflammatory (19 elbows) or haemophilic (3 elbows) diseases, in order to evaluate: 1) functional result and mobility; 2) frequency of loosening. The results were evaluated after an average of 36 months [16-67] by an observer who took part neither in therapeutic decisions, nor in surgery. Twenty elbows were associated with severe pain before surgery, while 16 elbows were painless and 5 had occasional pain at follow-up. The range of flexion was 133 degrees (from 96 degrees to 50 degrees) and the average range of extension was 32 degrees (extension ranged from [-10 to -90 degrees]). Only 2 elbows had a range of pronation-supination less than 100 degrees, the average range of pronation was 75 degrees (from [30 degrees to 90 degrees]) and 75 degrees (from [20 degrees to 90 degrees]) in supination. The functional results were comparable for the two types of prostheses. We observed 2 postoperative dislocations (1 GSB III and 1 Kudo) which were stabilized after surgical revision; and one late dislocation (1 GSB III) related to friction-wear. We identified incomplete ossification between the humerus and ulna in the 8 GSB III and 10 of the 14 Kudo. A reduction of 20 degrees in all mobility sectors was identified with the Kudo when ossifications were observed. Two implants became loose : the two pieces of 1 GSB III and the ulnar piece of 1 Kudo. One humeral piece of Kudo was broken at the junction between the stem and the trochlea. Three other GSB III had severe osteolysis which could compromise fixation or subsequent prosthetic revision. For the inflammatory and haemophilic arthropathies, the elbow prosthesis gave painless and satisfactory mobility for the short and medium term. The loosening of the 22 prostheses and the frequency of osteolysis with the GSB III (3/8) justify a longer follow-up.

[Fatigue rupture of a Harris-Galante shell in contact with an autograft of the femur head. Analysis of bone, mechanical and metallurgical factors]

We observed, after 38 months of follow-up, the rupture of the metallic shell of a Harris-Galante cup implanted in a dysplastic acetabulum augmented with a femoral head autograft. Bone ingrowth was extended to 53% of the porous surface, but only in the areas in contact with the true acetabulum. No bone ingrowth was identified in the fiber mesh in contact with the autograft. The graft was necrotic on histologic examination and showed collapse radiographically. These last conditions were responsible for shear stress in the part of the cup that was in contact with the graft-acetabulum junction. These stresses were involved in the fatigue rupture mechanism identified on microscopic examination of rupture surfaces. We observed metallic structure anomalies in the failed cup by comparing with another Harris-Galante cup considered as a reference: larger alpha elements, reduction of the titanium equiaxial structure. These defects could be related to uncontrolled temperature during the sintering process utilized for fiber mesh fixation. These structural anomalies, by reducing the metallic fatigue strength, potentiated the deleterious effect of partial bone ingrowth and graft collapse.

Effect of graft position on laxity after anterior cruciate ligament reconstruction. Stress radiography in 90 knees 2 to 5 years after autograft

The effect of tibial and femoral graft placement on radiographic laxity after anterior cruciate ligament reconstruction was studied in 90 knees. All the knees were operated according to the Marshall-MacIntosh procedure with a through-the-condyle technique. Graft position and laxity were determined on lateral x-rays (static and mechanically assisted 200 Newtons anterior drawer strain). No relation was observed between tibial tunnel position and radiographic laxity. In fact few variations in placement were recorded. Femoral tunnel placement was more dispersed, and it strongly influenced the radiographic laxity (p = 0.0001). Laxity was minimal when the center of the femoral tunnel was 6 mm below the intercondylar notch roof and 2.5 mm behind the posterior margin of the notch. No correlations were observed between tunnel positions and function evaluated with the ARPEGE score. These results stressed the importance of the femoral graft placement to control laxity after anterior cruciate ligament reconstruction, and allowed determination in vivo of a position for which minimal laxity could be expected. Since the method determining the femoral graft placement in the present study was not precise, we now use fluoroscopic control to determine drill-guide position.