The resisted torsional stress test in diagnosis of femoral stem loosening in uncemented total hip arthroplasty - first description and retrospective study.

INTRODUCTION: Aseptic femoral stem loosening is among the most common causes for revision in total hip arthroplasty (THA). We describe a simple clinical test that triggers pain in the proximal femur in patients with a loose stem. A previously described passive rotation test was associated with a poor sensitivity. The resisted torsional stress test (RTST) was used for several years in our hospital, and this is the first description of its reliability. METHODS: We retrospectively reviewed our database of uncemented stem revisions. Preoperative clinical reports were searched for data on the RTST. A positive RTST was defined as sharp pain felt at the stem level with active internal rotation against a passive external rotation impulse in 90° hip flexion. The definition of stem fixation (fixed vs. loose) was made by readout of the surgery reports. RESULTS: The RTST was reported in 83 cases and was positive in 32 of the 43 stems, which were found loose intraoperatively and in 9 of the 40 stems, which were well integrated. This leads to an accuracy of classification of 79.5%. The sensitivity was 80% and the specificity was 79.1%. PPV and NPV were 78% and 81%, respectively. CONCLUSION: The RTST provides a helpful tool in the clinical assessment of femoral stem fixation in THA with good accuracy and should be included in standard follow-up examinations and in the assessment of painful THAs.

The early outcome of surgical treatment for femoroacetabular impingement: success depends on how you measure it.

OBJECTIVE: To evaluate the proportion of "successes" after surgery for femoroacetabular impingement (FAI) using different external criteria, "feeling better" and "feeling good", and to determine the corresponding cut-off scores indicating "success" for the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) (0-10-point response scale), Oxford Hip Score (OHS) and EuroQoL-5D (EQ-5D and EQ-VAS). DESIGN: Prospective, observational study based in an orthopaedic hospital. Ninety-nine consecutive patients with FAI completed the questionnaires before and 6 months after surgery (arthroscopy or mini-open surgical dislocation). Patient-ratings of change in state ("feeling better") were assessed using a global treatment outcome (GTO) item. Acceptability of the current health state was assessed using the symptom-specific well-being (SSWB) item. Cut-off (threshold) scores for the different instruments indicating the minimal clinically important change (MCIC) and acceptable symptom state were calculated using Receiver Operating Characteristics (ROC) analyses. RESULTS: Significant improvements in all scores (P < 0.001) were recorded 6 months after surgery. The proportion of good outcomes measured with GTO was 60%; 55% of patients reported having achieved an acceptable symptom state. The MCIC scores for improvement were ≥6 for the OHS (0-48 total score range), ≥15 for EQ-VAS, ≥0.16 for EQ-5D index, and ≥22 for the WOMAC-total score (0-100 total score range); absolute scores of ≥40, ≥80, ≥0.682 and ≤8, respectively, were associated with an acceptable symptom state. CONCLUSIONS: The results show that feeling better does not always equate to feeling good, and that improvements in outcome scores, even large, do not necessarily indicate acceptability of the current state. The cut-off values may help in the interpretation of trial results and individual change-scores recorded in clinical practice.

[Diagnosis and therapy of hip abductor insufficiency after hip arthroplasty]. / Diagnostik und Therapie von Funktionsstörungen der Hüftmuskulatur nach Totalendoprothese.

Abductor insufficiency after hip arthroplasty is a difficult and challenging problem whereby conservative therapy is often insufficient and surgical therapy is known to have failures with re-ruptures. Alternative approaches and arthroscopic surgery are proposed but in many cases they do not fulfill the expectations of patients.Our experience with temporary explantation of implants and transosseous refixation is good resulting in a pain-free patient in a high number of cases but the method is quite demanding and needs a cooperative patient. A functionless abductor muscle is not amenable to surgical treatment but only a surgical exploration can confirm the clinical suspicion.

Isolated rupture of the subscapularis tendon.

Sixteen consecutive patients were managed operatively for repair of an isolated traumatic rupture of the subscapularis tendon in the absence of avulsion of the lesser tuberosity. All of the patients were men. The diagnosis was made for each patient on the basis of the clinical examination and was confirmed by imaging studies and operative exploration. The operative treatment consisted of mobilization of the subscapularis after exploration and protection of the axillary nerve, transosseous reinsertion of the tendon to a trough created at the lesser tuberosity, closure of the rotator interval, and protection of the shoulder for six weeks postoperatively. The average duration of follow-up was forty-three months (range, twenty-four to eighty-four months). Thirteen patients subjectively rated the result as excellent or good. The average functional score of the shoulder, as assessed according to the system of Constant, was 82 per cent of the average age and gender-matched normal value. Active flexion was normal in twelve patients, was decreased by 15 degrees or less in three, and was severely limited in one patient. The capacity of the patients to work in their original occupations had increased from an average of 59 per cent of full capacity preoperatively to an average of 95 per cent postoperatively (p = 0.006). Operative treatment proved to be economically sound within the Swiss National Accident Insurance system. The quality of the result did not depend on the capacity for work at the time of the operation, on the type of work in which the patient was engaged, on the state of the biceps, or on the duration of follow-up. Conversely, the results were less successful when there was an increased delay from the time of the injury to the time of the operative repair.

Iatrogenic displacement of fracture-dislocations of the shoulder. A report of seven cases.

We report seven cases in which open or closed reduction of a shoulder dislocation associated with a fracture of the humeral neck led to displacement of the neck fracture. Avascular necrosis of the humeral head developed in all six patients with anatomical neck fractures. All five anterior dislocations also had a fracture of the greater tuberosity and both posterior dislocations had a fracture of the lesser tuberosity. The neck fracture had not initially been recognised in three of the seven cases. In five cases attempted shoulder reduction led to complete displacement of the head segment, which was treated by open reduction and minimal internal fixation. In the other two cases, shoulder reduction caused only mild to moderate displacement which was accepted and the fracture was treated conservatively. We conclude that biplane radiography is essential before reduction of a shoulder dislocation. Neck fractures must always be ruled out, especially where there are tuberosity fractures. In our series, careful closed reduction under general anaesthesia with optimal relaxation and fluoroscopic control did not prevent iatrogenic displacement. Prophylactic stabilisation of the neck fracture should be considered before reduction of such a fracture-dislocation. It may be, however, that the prevention of displacement by prophylactic stabilisation does not always prevent late avascular necrosis; we observed this in one case.

Periacetabular osteotomy in the treatment of neurogenic acetabular dysplasia.

We carried out the Bernese periacetabular osteotomy for the treatment of 13 dysplastic hips in 11 skeletally mature patients with an underlying neurological diagnosis. Seven hips had flaccid paralysis and six were spastic. The mean age at the time of surgery was 23 years and the mean length of follow-up was 6.4 years. Preoperatively, 11 hips had pain and two had progressive subluxation. Before operation the mean Tönnis angle was 33 degrees, the mean centre-edge angle was -10 degrees, and the mean extrusion index was 53%. Postoperatively, they were 8 degrees, 25 degrees and 15%, respectively. Pain was eliminated in 7 patients and reduced in four in those who had preoperative pain. One patient developed pain secondary to anterior impingement from excessive retroversion of the acetabulum. Four required a varus proximal femoral osteotomy at the time of the pelvic procedure and one a late varus proximal femoral osteotomy for progressive subluxation. Before operation no patient had arthritis. At the most recent follow-up one had early arthritis of the hip (Tönnis grade I) and one had advanced arthritis (Tönnis grade III). Our results suggest that the Bernese periacetabular osteotomy can be used successfully to treat neurogenic acetabular dysplasia in skeletally mature patients.

Tendon transfers for the treatment of irreparable rotator cuff defects.

Certain defects of the rotator cuff musculotendinous units cannot be repaired. If restoration of strength is an important treatment goal, then tendon transfers must be considered for palliation. In this article, the anatomical and physiological bases for tendon transfers are discussed, and currently known results with this form of treatment are reviewed.

Pathomorphologic characteristics of posttraumatic acetabular dysplasia.

OBJECTIVES: The pathomorphology of posttraumatic acetabular dysplasia differs fundamentally from the classic developmental dysplasia of the adolescent. The aim of this report is to qualify and quantify the pathomorphologic characteristics of the posttraumatic acetabular dysplasia and to define the requirements for adequate corrective surgery in this type of dysplasia. DESIGN AND MATERIAL: Retrospective review of the anteroposterior (AP) radiographs of ten patients with symptomatic posttraumatic acetabular dysplasia. In five cases, false profile views and in five cases computed tomography (CT) scans were also available for investigation. Measurements of distances and angles on radiographs and CT scans were made by pencil and goniometer. RESULTS: On the AP radiographs, posttraumatic acetabular dysplasia shows uniformly deformed true pelvis with an angular deformation of the innominate bone averaging 20 degrees in the region of the acetabular fossa that causes the concavity of the pelvic brim to increase in direction of the involved acetabulum and creates both a lateral and a caudal displacement of the acetabulum, averaging twenty-three millimeters and nine millimeters, respectively. The increased width of the inner wall of the acetabulum, measuring an average of eleven millimeters, makes lateralization of the center of the femoral head reach a mean of forty-three millimeters. The acetabular deformity in all cases shows a pronounced lateral deficiency. Ventral deficiency is moderate. All ten posttraumatic dysplastic acetabuli show marked retroversion averaging 27 degrees. In contrast, the contralateral acetabuli shows a mean anteversion of 23 degrees. CONCLUSIONS: The morphology of this kind of acetabular dysplasia is uniform and differs significantly from that seen in classic developmental dysplasia of the hip. For reconstructive surgery of such a hip, the challenge to abolish the lateralization of the hip joint to restore normal body weight lever arm is imperative. Because acetabular retroversion is a reproductive feature of posttraumatic dysplasia, it is important to avoid further reduction of the posterolateral containment of the femoral head and augmentation of the anterior acetabular wall, increasing the risk of anterior impingement.

8-year survivorship analysis and subjective results of 687 primary Balgrist hip sockets.

The Balgrist hip socket consists of an outer split ring in the form of a truncated cone, made of titanium, which is expanded by a tapered HDPE insert during implantation, thus ensuring firm primary press-fit and the possibility of retightening in the postoperative remodelling phase. Between November 1987 and October 1996, 687 primary Balgrist hip sockets were implanted in 555 patients. Five hundred and thirty-seven patients were investigated. Of these patients, 71.1% never had pain in the operated hip, 88.1% had no problems putting on their shoes, 76.2% were able to walk one or more hours. Furthermore, 91.7% are very or mostly content with the postoperative result. Nineteen hip sockets had to be revised until April 1997. With a 92.1% Kaplan-Meier survivorship rate after 8 years the Balgrist hip socket ranks among the most successful noncemented acetabular components.

The Bernese periacetabular osteotomy for the treatment of adult hip dysplasia.

The Bernese periacetabular osteotomy was developed for precise spatial reorientation of the adult dyplastic acetabulum and improvement of the femoral head coverage. The osteotomy has a large correction potential (average decrease of acetabular index: 22 degrees) but is technically demanding. With appropriate patient selection, the results obtained are promising. Therefore, the technique described should be considered in the treatment plan for the acetabular dysplasia of the young adult.

Use of multimodal intra-operative monitoring in averting nerve injury during complex hip surgery.

Peripheral nerve injury is an uncommon but serious complication of hip surgery that can adversely affect the outcome. Several studies have described the use of electromyography and intra-operative sensory evoked potentials for early warning of nerve injury. We assessed the results of multimodal intra-operative monitoring during complex hip surgery. We retrospectively analysed data collected between 2001 and 2010 from 69 patients who underwent complex hip surgery by a single surgeon using multimodal intra-operative monitoring from a total pool of 7894 patients who underwent hip surgery during this period. In 24 (35%) procedures the surgeon was alerted to a possible lesion to the sciatic and/or femoral nerve. Alerts were observed most frequently during peri-acetabular osteotomy. The surgeon adapted his approach based on interpretation of the neurophysiological changes. From 69 monitored surgical procedures, there was only one true positive case of post-operative nerve injury. There were no false positives or false negatives, and the remaining 68 cases were all true negative. The sensitivity for predicting post-operative nerve injury was 100% and the specificity 100%. We conclude that it is possible and appropriate to use this method during complex hip surgery and it is effective for alerting the surgeon to the possibility of nerve injury.

Passive tension in the supraspinatus musculotendinous unit after long-standing rupture of its tendon: a preliminary report.

Incomplete functional recovery after rotator cuff surgery can be caused by rerupture or incomplete restoration of the contractile properties of the muscle-tendon-bone unit. We measured the passive tension generated in the supraspinatus musculotendinous unit at the time of repair of the supraspinatus tendon performed for the treatment of long-standing rupture in four patients and compared our results with the values of an intact musculotendinous unit. In stepwise elongation from 10 to 20 mm, passive tension increased by a factor of 2.2 +/- 0.4 in the study group. In the control case passive tension increased by a factor of only 1.3. Mean tension in 60 degrees of abduction was 14.25 +/- 3.4 N in the four long-standing ruptures and 10 N in the control case. If the arm was brought to the side, tension rose to 25 N in the control case, whereas mean tension increased to 59.25 +/- 12.7 N in long-standing rupture of the supraspinatus muscle. Our findings demonstrate that passive tension in the supraspinatus is increased after long-standing rupture of its tendon. This result suggests that active force generation by this muscle will be compromised after surgery and that the high strain after repair may expose the musculotendinous unit to further damage.

[Follow-up and prognosis of neurologic sequelae of pelvic ring fractures with involvement of the sacrum and/or the iliosacral joint]. / Verlauf und Prognose von neurologischen Ausfällen nach Beckenringfrakturen mit Beteiligung des Os sacrum und/oder Iliosakralgelenks.

The extent of neurological lesions following an injury of the pelvic ring is often not initially recognized, as interest is then focused on the treatment of the pelvic ring fracture. Once the fracture has healed, the patient suffers from the sequelae of the neurological injury. Our series of 323 pelvic ring injuries includes 161 sacral fractures and 12 complete disruptions of the sacroiliac joint. Twenty-three patients sustained an injury of the lumbosacral plexus, and 20 patients were examined retrospectively. The different parts of the lumbosacral plexus showed variable recovery potential. An important or complete recovery was noted in 8 of 9 patients suffering from a motor deficit of the lumbar plexus, the obturator nerve, the superior gluteal nerve or the inferior gluteal nerve. Four out of 8 patients with a motor deficit of the sacral plexus had an important or complete improvement. In contrast to these results was the poor recovery of lesions of the lumbosacral trunk. Eight out of 11 patients showed no or only minor recovery, although the pelvic ring was stabilized by operative means in 9 patients. In 2 patients the lumbosacral trunk was directly decompressed by a dorsal approach. In both cases the recovery was complete. In 6 patients the sphincter function was damaged. Recovery was dependent on the localization of the sacral fracture. If the fracture traversed the sacral canal, no neurological improvement was noted.

Failure of reinserted short external rotator muscles after total hip arthroplasty.

The frequency and point in time of failure of repaired short external rotator muscles were determined in 27 total hip arthroplasties. The piriformis, triceps coxae, and obturator externus muscles were released close to the trochanter and reattached only if tension was low and if the tendon tissue allowed a good hold for anchoring the stitch. A radiopaque marker was attached to each side of the suture with maximum 1-cm distance between opposite markers. The distance between markers was determined on radiographs obtained 1 day and 3 months postoperatively; >/=2.5 cm indicated failure. Of 50 repaired short external rotator muscles, 35 (70%) failed-26 within the first day and 9 within 3 months postoperatively. In 2 hips, no failure of the repaired short external rotator muscles was observed. Repair of the short external rotator muscles after total hip arthroplasty contributes little to prevention of hip dislocation.

Indications for intertrochanteric osteotomy after periacetabular osteotomy for adult hip dysplasia.

Residual hip dysplasia in the adult is characterized by deficient anterior and lateral acetabular coverage with subsequent hip joint incongruity and instability. The frequency of periacetabular osteotomy for the treatment of residual hip dysplasia is increasing. In certain morphologic conditions preoperative abduction or intraoperative radiographs reveal that congruency after a periacetabular osteotomy is not optimum; at this point the surgeon may consider the addition of an intertrochanteric osteotomy. In a retrospective study, the radiographs of 25 patients who had a femoral osteotomy with or after periacetabular osteotomy were analyzed and the results were compared with a control group of 34 patients who had periacetabular osteotomy without a femoral osteotomy. The analyzed parameters included: the femoral head extrusion index and the acetabular index, before and after periacetabular osteotomy; the femoral neck shaft angle; the presence of femoral head deformity; the presence of osteoarthrosis; the presence of a secondary acetabulum; the influence of previous ipsilateral hip surgery; the effect of hip adduction or abduction on joint congruency; and the age of the patient. The variables that had a statistically significant association with the performance of an intertrochanteric osteotomy included a femoral head extrusion index and an acetabular index after periacetabular osteotomy outside the normal limits, a neck shaft angle outside the limits of the control group, a deformed femoral head, an osteoarthritic hip, a secondary acetabulum, and a joint space height and congruency dependent on position of the proximal femur. When using statistically significant variables, a discriminant analysis predicted the correct group (periacetabular osteotomy with femoral osteotomy, or periacetabular osteotomy without femoral osteotomy) for 89% of the cases.

The clinical relevance of posttraumatic avascular necrosis of the humeral head.

Twenty-five patients with a partial or complete collapse of the humeral head caused by post-traumatic avascular necrosis underwent clinical and radiologic evaluation at an average of 7.5 years (range 2.3 to 17.6 years) after having an underlying proximal humeral fracture. Posttraumatic humeral head necrosis was always associated with disability. The overall shoulder function as assessed with the Constant score was 46 points, corresponding to a functional shoulder value of 51% of an age- and sex-matched normal control group. The clinical outcome was significantly related to the anatomic alignment of the fragments of the humerus by the time of healing. In 13 patients (group 1) treatment resulted in an anatomic or nearly anatomic healing of the fracture, and in 12 other patients (group 2) avascular necrosis and collapse ensued in addition to malunion of 1 or more of the fracture fragments. Subjective overall outcome (P < .0001) and pain (P < .0001) were significantly better in group 1. Active anterior elevation averaged 125 degrees in group 1 and 80 degrees in group 2 (P = .0007), and abduction averaged 110 degrees in group 1 and 63 degrees in group 2 (P = .007). The relative shoulder score according to Constant was 65% of an age- and sex-matched normal population for group 1 and 41% for group 2 (P = .001). The results obtained in group 1 were comparable to those reported after hemiarthroplasty for complex humeral fractures. A proximal humeral fracture that is at risk for avascular necrosis has to be reduced anatomically if joint-preserving treatment is selected. If anatomic reduction cannot be obtained, other treatment options such as arthroplasty should be considered.

[4 fragment fractures of the proximal femur: is the dynamic hip screw a suitable implant?]. / 4-Fragment-Frakturen des proximalen Femurs: Ist die dynamische Hüftschraube (DHS) ein geeignetes Implantat?

The DHS-implant system is widely used in the operative treatment of pertrochanteric fractures of the femur. The telescoping effect of the implant in the unstable 4-fragment fracture leads to lateralisation of the greater trochanter and shortening of the leg. The quality of reposition influences this secondary dislocation. In our series of 65 patients treated with this device 17 repositions were in a varus position, followed by leg shortening of more than 10 mm in 9 patients. Independent of the quality of reposition in the long-term follow-up only one patient of 25 complained of persistent pain.

The pattern of pain produced by irritation of the acromioclavicular joint and the subacromial space.

To characterize the patterns of pain caused by selective irritation of the acromioclavicular joint and of the subacromial space, hypertonic saline solution was injected 15 times into the acromioclavicular joints of 10 healthy volunteers and 10 times into the subacromial space of 9 healthy volunteers. Irritation of the acromioclavicular joint produced pain directly over the joint, in the antero-lateral neck, in the trapezius-supraspinatus region, and in the anterolateral deltoid. Irritation of the subacromial space produced pain in the region of the lateral acromion, the deltoid muscle, and occasionally in the forearm or the fingers but did not produce pain in the neck or in the trapezius region. Neither acromioclavicular nor subacromial irritation produced pain at the posterior aspect of the shoulder. This information may assist in accurate clinical diagnosis and in the selection of optimal imaging studies for the evaluation of shoulder pain.

[Avascular femur head necrosis as severe complication after femoral intramedullary nailing in children and adolescents]. / Die avaskuläre Hüftkopfnekrose als schwerwiegende Komplikation nach Femurmarknagelung bei Kindern und Jugendlichen.

Nailing of femoral fractures before closure of the growth plates may lead to avascular necrosis of the femoral head in 3-4% of cases. In addition to the 14 cases described in the literature we present 3 more. Analysis of these cases reveals a common pathogenesis. The nails were all inserted anterograde and were designed for the adult femur. The problem appears to be related to the large diameter of the nail and its entry point in the relatively small femoral neck basis, close to the vessels supplying the femoral head. The role of the open physis remains unclear. Even though the complication of femoral head necrosis is rare, it is a severe complication. Therefore we do not recommend anterograde femoral nailing, using the classic entry point, in children or adolescents. We believe that there is a need for a new design of femoral nail. If both femoral head necrosis and coxa valga are to be avoided, we suggest that the entry point of the nail should be dorsolateral, below the trochanteric physis.