Semiconstrained primary and revision total elbow arthroplasty with use of the Coonrad-Morrey prosthesis

BACKGROUND: Semiconstrained total elbow prostheses are used routinely by many surgeons to treat a variety of severe elbow disorders. Our objective was to review the results of primary and revision total elbow arthroplasty with use of the Coonrad-Morrey prosthesis. The selected use of this semiconstrained implant in patients with instability and poor bone stock was hypothesized to provide inferior results compared with those in the published reports. METHODS: The results of sixty-seven semiconstrained total elbow arthroplasties that were performed in fifty-six patients between 1990 and 2003 were evaluated. Thirty-seven elbows had a primary arthroplasty and were followed for a mean of eighty-six months, and thirty elbows had a revision arthroplasty and were followed for a mean of sixty-eight months. Mayo elbow performance scores and radiographic analyses were used to assess the clinical results. RESULTS: In the primary arthroplasty group, the average flexion improved from 116 degrees to 135 degrees; average extension, from -40 degrees to -33 degrees; average pronation, from 60 degrees to 81 degrees; and average supination, from 60 degrees to 69 degrees. The improvements in flexion and pronation were significant (p<0.001 for both). Preoperatively, twenty-five (74%) of thirty-four elbows with data available had moderate or severe pain, whereas only four (11%) had pain postoperatively. The average postoperative Mayo score (and standard deviation) was 84+/-16. Eleven of the thirty-seven primary replacements failed, and the five-year survival rate was 72%. In the revision arthroplasty group, average flexion improved from 124 degrees to 131 degrees; average extension, from -32 degrees to -22 degrees; average pronation, from 66 degrees to 75 degrees; and average supination, from 64 degrees to 76 degrees; the improvement in supination was significant (p<0.05). Preoperatively, eighteen (64%) of the twenty-eight elbows with data available had moderate or severe pain, while only five (17%) had pain postoperatively. The average postoperative Mayo score was 85+/-16. Eleven of the thirty revision replacements failed, and the five-year survival rate was 64%. CONCLUSIONS: A Coonrad-Morrey semiconstrained total elbow arthroplasty provides excellent pain relief and good functional return in patients with severe destructive arthropathy. The higher prevalence of failure in this cohort compared with series reported elsewhere is likely due to adverse patient selection as this implant was reserved for more complex arthroplasties with severe bone loss and ligamentous laxity.     

Constrained total scapula reconstruction after resection of a high-grade sarcoma

Patients with high-grade sarcomas arising from the scapula or periscapular soft tissues traditionally have been treated with either a total scapulectomy or a wide, en bloc, extraarticular scapular resection, termed the Tikhoff-Linberg resection. The major challenge after such resections is to restore shoulder girdle stability while preserving a functional hand and elbow. The current authors describe three patients who had an extraarticular, total scapula resection (modified Tikhoff-Linberg) for a high-grade sarcoma. Each patient had reconstruction with a constrained (rotator cuff-substituting) total scapula prosthesis in an effort to optimally restore the normal muscle force couples of both glenohumeral and scapulothoracic mechanisms. At latest followup, the Musculoskeletal Tumor Society functional score was 24 to 27 of 30 (80%-90%). All patients had a stable, painless shoulder and functional hand and elbow. Forward flexion and abduction ranged from 25 degrees to 40 degrees. Glenohumeral rotation (internal rotation, T6; external rotation -10 degrees) below shoulder level, shoulder extension, and adduction were preserved. Protraction, retraction, elevation, and abduction of the scapula were restored and contributed to shoulder motion and upper extremity stabilization. There were no complications. Total scapula reconstruction with a constrained total scapula prosthesis is a safe and reliable method for reconstructing the shoulder girdle after resection of select high-grade sarcomas. The authors emphasize the clinical indications, prosthetic design, surgical technique, and early functional results.     

The effect of screw position on the initial fixation of a reverse total shoulder prosthesis in a glenoid with a cavitary bone defect

Patients with rotator cuff tear arthropathy can be treated successfully with a reverse total shoulder prosthesis. In patients with significant glenoid bone loss, achieving stable bone fixation can be challenging, as the surgeon must know when bone grafting is necessary and when the plan to implant the reverse total shoulder prosthesis should be abandoned because of the likelihood of early implant loosening. The purposes of this study were (1) to determine the initial stability of a metal glenoid implant fixed in a glenoid with a central cavitary defect and (2) to determine whether an altered screw configuration would sufficiently resist implant micromotion and, thereby, allow bone ingrowth to occur. The Delta III reverse total shoulder glenoid implant was fixed into foam scapulae with a uniform density similar to normal glenoid bone density. The control group implants were fixed into foam scapulae without a glenoid defect, by use of the standard surgical technique for screw placement. The second group was fixed into foam scapulae containing a central cavitary glenoid defect, by use of the standard surgical technique for screw placement. The central cavitary defect was meant to simulate the bone loss typically found after the removal of a loose pegged glenoid implant, and it was created with a 4-pegged glenoid drill guide. A third group was fixed into foam scapula with a central cavitary glenoid defect, with an experimental screw configuration by use of a posterior screw directed toward the spine of the scapula and an anterior screw directed inferior to the central peg. All specimens were loaded with 500 cycles of 1 body weight (70 kg) to simulate the forces generated during arm elevation that occur during the first 3 months after surgery. Micromotion between the implant and the foam bone was measured with a digital video motion analysis system (accuracy, +/- 2.6 microm). After loading of the implant with 70 kg for 500 cycles in the superior direction, the mean micromotion was 54 microm (SD, 22) in the control group, 159 microm (SD, 70) in the second group, and 86 microm (SD, 32) in the third group (P = 0.003). Fixing the posterior screw into the spine of the scapula and directing the anterior screw below the central peg decreased the micromotion of a metal glenoid implant fixed in a glenoid with a cavitary defect by 46% and, more importantly, reduced the micromotion below the critical threshold of 150 microm, which is necessary for bone ingrowth and long-term survival of the implant.     

不同程度屈膝挛缩畸形人工全膝关节置换的早期疗效比较

目的探讨不同程度屈膝挛缩畸形行人工全膝关节置换术(totalkneearthroplasty,TKA)后的早期疗效。方法回顾性分析2000年1月～2003年12月行TKA的65例97膝屈膝挛缩畸形患者资料。其中骨关节炎51例74膝,类风湿关节炎14例23膝。单膝置换33例33膝,双膝同时置换32例64膝。按屈膝挛缩畸形程度不同将患者分成A、B两组,A组屈曲挛缩<20°(0～15°)32例49膝,B组屈曲挛缩≥20°(20～60°)33例48膝。A、B两组膝关节术前屈曲挛缩度数、活动度(rangeofmotion,ROM)、KSS(kneesocietyscore)评分及功能评分分别为10.7±8.0°、104.6±20.0°、29.1±18.0、32.6±20.7和28.2±7.8°、60.8±26.6°、12.1±13.2、26.8±18.1,各指标组间比较差异均有统计学意义(P<0.05)。术中均采用Scorpio后稳定型骨水泥固定假体,行初期置换。术后3～4d在同一康复师指导下行CPM及主动功能锻炼。结果患者获随访8个月～3年6个月,平均2年7个月。A、B组术后膝关节屈曲挛缩度数、ROM、KSS评分和功能评分分别为0.4±2.1°、108.6±19.0°、82.1±13.8、72.3±29.1和1.3±3.2°、98.6±16.4°、75.9±8.2、81.4±26.9,组间比较差异均无统计学意义(P>0.05)。术后患者总满意度为94.6%,无深部感染及再翻修者。结论膝关节屈膝挛缩畸形严重与否对TKA的早期疗效无明显影响;TKA后ROM有“趋中”现象;术后早期行膝关节功能锻炼也是获得功能改善的重要环节之一。     

Arthroplasty with a metal radial head for unreconstructible fractures of the radial head

BACKGROUND: Treatment of unreconstructible comminuted fractures of the radial head remains controversial. There is limited information on the outcome of management of these injuries with arthroplasty with a metal radial head implant. METHODS: The functional outcomes of arthroplasties with a metal radial head implant for the treatment of twenty-five displaced, unreconstructible fractures of the radial head in twenty-four consecutive patients (mean age, fifty-four years) were evaluated at a mean of thirty-nine months (minimum, two years). There were ten Mason type-III and fifteen Mason-Johnston type-IV injuries. Two of these injuries were isolated, and twenty-three were associated with other elbow fractures and/or ligamentous injuries. RESULTS: At the time of follow-up, Short Form-36 (SF-36) summary scores suggested that overall health-related quality of life was within the normal range (physical component = 47 +/- 10, and mental component = 49 +/- 13). Other outcome scales indicated mild disability of the upper extremity (Disabilities of the Arm, Shoulder and Hand score = 17 +/- 19), wrist (Patient-Rated Wrist Evaluation score = 17 +/- 21 and Wrist Outcome Score = 60 +/- 10), and elbow (Mayo Elbow Performance Index = 80 +/- 16). According to the Mayo Elbow Performance Index, three results were graded as poor; five, as fair; and seventeen, as good or excellent. The poor and fair outcomes were associated with concomitant injury in two patients, a history of a psychiatric disorder in three, comorbidity in two, a Workers' Compensation claim in two, and litigation in one. Subjective patient satisfaction averaged 9.2 on a scale of 1 to 10. Elbow flexion of the injured extremity averaged 140 degrees +/- 9 degrees; extension, -8 degrees +/- 7 degrees; pronation, 78 degrees +/- 9 degrees; and supination, 68 degrees +/- 10 degrees. A significant loss of elbow flexion and extension and of forearm supination occurred in the affected extremity, which also had significantly less strength of isometric forearm pronation (17%) and supination (18%) as well as significantly less grip strength (p < 0.05). Asymptomatic bone lucencies surrounded the stem of the implant in seventeen of the twenty-five elbows. Valgus stability was restored, and proximal radial migration did not occur. Complications, all of which resolved, included one complex regional pain syndrome, one ulnar neuropathy, one posterior interosseous nerve palsy, one episode of elbow stiffness, and one wound infection. CONCLUSIONS: Patients treated with a metal radial head implant for a severely comminuted radial head fracture will have mild-to-moderate impairment of the physical capability of the elbow and wrist. At the time of short-term follow-up, arthroplasty with a metal radial head implant was found to have been a safe and effective treatment option for patients with an unreconstructible radial head fracture; however, long-term follow-up is still needed.     

Treatment of painful pseudoparesis due to irreparable rotator cuff dysfunction with the Delta III reverse-ball-and-socket total shoulder prosthesis

BACKGROUND: The Delta III reverse-ball-and-socket total shoulder implant is designed to restore overhead shoulder function in the presence of irreparable rotator cuff deficiency by using the intact deltoid muscle and the stability provided by the prosthetic design. Our purpose was to evaluate the clinical and radiographic results of this arthroplasty in a consecutive series of shoulders with painful pseudoparesis due to irreversible loss of rotator cuff function. METHODS: Fifty-eight consecutive patients with moderate-to-severe shoulder pain and active anterior elevation of <90 degrees due to an irreparable rotator cuff tear were treated with a Delta III total shoulder replacement at an average age of sixty-eight years. Seventeen of the procedures were the primary treatment for the shoulder, and forty-one were revisions. The patients were examined clinically and radiographically after an average duration of follow-up of thirty-eight months. RESULTS: On the average, the subjective shoulder value increased from 18% preoperatively to 56% postoperatively (p < 0.0001); the relative Constant score, from 29% to 64% (p < 0.0001); the Constant score for pain, from 5.2 to 10.5 points (p < 0.0001); active anterior elevation, from 42 degrees to 100 degrees (p < 0.0001); and active abduction, from 43 degrees to 90 degrees (p < 0.0001). The patients for whom the implantation of the Delta III prosthesis was the primary procedure and those who had had previous surgery showed similar amounts of improvement. The total complication rate, including all minor complications, was 50%, and the reoperation rate was 33%. Of the seventeen primary operations, 47% (eight) were associated with a complication and 18% (three) were followed by a reoperation. Of the forty-one revisions, 51% (twenty-one) were associated with a complication and 39% (sixteen) were followed by a reoperation. Subjective results and satisfaction rates were not influenced by complications or reoperations when the prosthesis had been retained. CONCLUSIONS: Total shoulder arthroplasty with the Delta III prosthesis is a salvage procedure for severe shoulder dysfunction caused by an irreparable rotator cuff tear associated with other glenohumeral lesions. Complications were frequent following both primary and revision procedures, but they rarely affected the final outcome. The procedure has a substantial potential to improve the condition of patients with severe shoulder dysfunction, at least in the short term.     

Grammont inverted total shoulder arthroplasty in the treatment of glenohumeral osteoarthritis with massive rupture of the cuff. Results of a multicentre study of 80 shoulders

We reviewed 80 shoulders (77 patients) at a mean follow-up of 44 months after insertion of a Grammont inverted shoulder prosthesis. Three implants had failed and had been revised. The mean Constant score had increased from 22.6 points pre-operatively to 65.6 points at review. In 96% of these shoulders there was no or only minimal pain. The mean active forward elevation increased from 73 degrees to 138 degrees. The integrity of teres minor is essential for the recovery of external rotation and significantly influenced the Constant score. Five cases of aseptic loosening of the glenoid and seven of dissociation of the glenoid component were noted. This study confirms the promising early results obtained with the inverted prosthesis in the treatment of a cuff-tear arthropathy. It should be considered in the treatment of osteoarthritis with a massive tear of the cuff but should be reserved for elderly patients.     

Kinematics and laxity of the Souter-Strathclyde total elbow prosthesis

The motion pattern and laxity of 8 cadaveric elbows were recorded with a 3-dimensional electromagnetic tracking device before and after the Souter-Strathclyde total elbow prosthesis was implanted. The Souter-Strathclyde prosthesis replicates the valgus-varus motion pattern of the intact elbow but causes a significant internal rotation of the ulnar shaft of 8.9 degrees +/- 4.1 degrees (P < .0005) at 110 degrees of elbow flexion. One of the reasons for this unphysiological motion pattern is positioning of the humeral component in a mean of 5.4 degrees +/- 6.4 degrees of external rotation compared with the intact elbow (P = .05). This positioning is related to the design of this device. The Souter-Strathclyde elbow prosthesis has a mean maximum valgus-varus laxity of 6.5 degrees +/- 1.5 degrees compared with 4.3 degrees +/- 2.3 degrees for the intact elbow (P = .004). This implant is more constrained than previously tested devices, which may explain its relatively higher loosening rate.     

Alumina ceramic prosthesis arthroplasty of the metacarpophalangeal joint in the rheumatoid hand. A 2-4-year follow-up study

Swanson's finger implant is being widely used to improve deformity of the thumb and finger and to restore function in the rheumatoid hand. Breakage of the implant and implant synovitis have been the most troublesome complications. The authors developed an alumina ceramic finger prosthesis to lessen these complications. This prosthesis was used for the metacarpophalangeal joint in 5 cases of flexion deformity of the thumb and in 21 cases (82 digits) with ulnar drift deformity. These cases were followed for 24-62 months (average, 38 months). Postoperative extension of the thumb was limited to 18 degrees and flexion was 48 degrees, on average. Postoperative range of motion was 30 degrees. The average limitation of extension of all digits was 18 degrees, and the average flexion was 54.5 degrees. The average range of motion was 36.5 degrees. Flexion deformity of the metacarpophalangeal joint of the thumb disappeared after operation, and ulnar drift was reduced to less than 10 degrees deviation in 87.8%. No dislocation or fracture of the prosthesis has been found on roentgenologic examination during short-term follow-up study. This prosthesis is useful for reducing deformity of the thumb and the finger in the rheumatoid hand. Postoperative extension of the metacarpophalangeal joint, however, has been unsatisfactory. The design of the prosthesis should be improved so that the rotational center of the metacarpophalangeal joint is located palmarly.     

Total elbow replacement with the GSB III prosthesis

Fourteen consecutive elbows have been treated for rheumatoid arthritis (9 elbows) and for post-traumatic osteoarthrosis (5 elbows) by total elbow replacement with the GSB III implant. The elbows were reviewed retrospectively after a mean follow-up of 6 years (2 to 9 years). Ten of 14 elbows had a functioning GSB III implant at follow-up; 7 of them were rated satisfactory and 3 unsatisfactory with the Mayo elbow performance score. In 5 of these 10 cases, the patients had significant pain relief with no or only mild pain at follow-up, whereas 5 had moderate to severe pain. With a functioning implant the range of motion averaged 140 degrees of flexion, 19 degrees of lack of extension, 65 degrees of pronation, and 84 degrees of supination. Six (43%) elbows had major complications requiring 1 to 8 additional operations. Aseptic loosening requiring revision occurred in 4 (29%) elbows. Two of them were treated by a resection arthroplasty, and 2 were revised with another hinged semiconstrained device. Three further elbows had radiolucent lines involving more than 50% of the cement-bone interface of either the humeral or the ulnar component. However, in 8 elbows the cementing technique was considered marginal or inadequate. Poor cementing (marginal or inadequate) was associated with loosening (P = .008). The GSB III total elbow prosthesis can restore function and reduce pain. The rate of aseptic loosening in this series was higher than previously reported. Based on this observation, we conclude that the GSB III implant seems to be sensitive to the insertion technique and does not tolerate suboptimal cementing.     

Clinical and radiological results of surgical removal of periarticular ossifications after hip prosthesis implantation

The occurrence of heterotopic ossification (HO) is a well-recognized problem after total hip replacement. In a retrospective study, we investigated 32 patients who had undergone surgical excision of symptomatic HO followed by radiation with 7 Gy and nonsteroidal anti-inflammatory drug therapy between 1994 and 1999. The mean follow-up was 20 months (range: 12-60). Clinical and radiographic follow-up examinations included Harris hip score and classification according to Brooker. The preoperative Brooker class was III in 16 cases and IV in 16 patients. Comparison of the Brooker classification at follow-up revealed a statistically significant improvement (p < 0.0001; class 0:3, class I: 14, class II: 8, class III: 7 patients). In one case with symptomatic Brooker class III ossification, surgical reexcision of HO was necessary. A statistically significant increase (p < 0.05) in mean range of motion (ROM) was observed in flexion [preoperative: 57 degrees (+/- 26), follow-up: 83 degrees (+/- 21)], in abduction [preoperative: 17 degrees (+/- 12), follow-up: 24 degrees (+/- 9)], and in rotation (preoperative: 16 degrees (+/- 17), follow-up: 31 degrees (+/- 18)]. Comparison of preoperative Harris hip score (60 +/- 11) and Harris hip score at the time of follow-up examination (73 +/- 17) revealed a statistically significant increase (p < 0.0001) after treatment. At the time of follow-up examination, 18 patients (56%) assessed their pain symptoms as low but 6 patients (19%) reported strong pain symptoms. Nevertheless, the score at the time of examination (35 +/- 10) was statistically improved (p < 0.02) when compared to the preoperative score (30 +/- 8). Surgical excision of Brooker class III or IV heterotopic ossification with limited ROM followed by irradiation and anti-inflammatory prophylaxis results in significant improvement in flexion, abduction, and rotation arc and significant reduction of HO in radiographic examination at follow-up, but pain relief was only satisfactory.     

影响全膝人工关节置换术后疗效的相关因素分析

目的分析后稳定型全膝人工关节置换（total knee replacement，TKR）术后疗效和并发症发生情况，探讨影响TKR术后疗效的相关因素。方法1998年1月～2004年8月，应用后稳定型膝关节假体对60例（74膝）骨性关节炎患者行TKR手术。以术后膝关节HSS（hospitl for special surgery）评分和各单项评分的改善率评定TKR术后疗效；比较有并发症和无并发症患者之间疗效优良率的差异；采用Pearson相关分析对TKR术后HSS评分与术前患者自身的有关因素进行相关性分析。结果60例患者获随访24～94个月，平均42．5个月。术后膝关节HSS评分、疼痛、功能、关节活动度、肌力、屈曲畸形及稳定性评分分别为84．2±14．2、25．7±6．9、17．9±4．3、13．1±2．0、9．2±0．8、8．1±0．4和9．3±0．1，较术前均有不同程度改善，尤以疼痛缓解最为明显，且差异均有统计学意义（P〈0．05）。疗效评定优良率为90．5％。10膝发生局部并发症，其中腓总神经损伤1膝，伤口愈合不良2膝，伤口感染、关节内感染及关节僵硬各1膝，症状性下肢深静脉血栓形成2膝，髌-股关节并发症2膝。有并发症患者膝关节优良率（60．0％）明显低于无并发症患者（95．3％），且差异有统计学意义（P〈0．05）。相关分析显示TKR术后HSS评分与膝关节术前HSS评分、疼痛和功能评分呈正相关，相关系数分别为0．523、0．431和0．418（P〈0．01）；而与患者术前关节活动度、肌力、屈曲畸形、稳定性、年龄、体重和体重指数等无相关（P〉0．05）。结论采用后稳定型TKR是治疗重症膝关节骨性关节炎的有效方法。术后疗效与术前膝关节HSS评分、疼痛和功能评分呈正相关；并发症的发生对术后疗效有明显负面影响。     

Long-term followup of uncemented tumor endoprostheses for the lower extremity.

Between 1982 and 1989, 100 primary lower limb reconstructions were done using the Kotz Modular Femur Tibia Reconstruction System after resection of a malignant tumor. In 32 patients a proximal femur prosthesis was implanted, in 40 patients a distal femur prosthesis was implanted, in 19 patients a proximal tibia component was implanted, in four patients a total femur prosthesis was implanted, and in five patients a total knee prosthesis was implanted. The Kaplan-Meier estimate of the overall survival rate of the prostheses was 85% after 3 years, 79% after 5 years, and 71% after 10 years. The most common reason for implant failure was aseptic loosening in 27% of patients (11 patients; range, 10-121 months) after the initial operation. The other reasons for revision surgery were implant fracture (n 5 4) and infection (n 5 4). Early repair of prostheses-related minor complications, such as worn polyethylene bushings, resulted in a statistically significant reduction of implant failure. After a median followup of 127.5 months after the initial surgery, 51 patients had died and eight patients were lost to followup. Forty-one patients were evaluated clinically and radiologically using the Musculoskeletal Tumor Society score and the radiologic implant evaluation system of the International Symposium on Limb Salvage; these 41 patients had a mean of 80% (range, 40%-100%) of the normal functional capability.     

Three-dimensional rotation of the scapula during functional movements: an in vivo study in healthy volunteers

The goal of this study was to measure 3-dimensional shoulder motion by use of a direct invasive technique during 4 different arm movements in healthy volunteers. Eight subjects with healthy shoulders were recruited. Optoelectronic marker carriers (ie, infrared light-emitting diodes) were mounted on bone pins, which were inserted into the lateral scapular spine. Subjects performed 4 different arm movements while the motion was being recorded by a precision optoelectronic camera. Joint angles were calculated in 3 dimensions. Intraclass correlation coefficients and root-mean-square differences were calculated as measures of reliability. During abduction, the scapula tipped posteriorly (44 degrees +/- 11 degrees), rotated upward (49 degrees +/- 7 degrees), and rotated externally (27 degrees +/- 11 degrees). For reaching, the scapula consistently rotated upward (17 degrees +/- 3 degrees) and rotated internally (18 degrees +/- 6 degrees) whereas tipping was generally less than 10 degrees (5 degrees +/- 2 degrees). Overall, the range of scapular movement for the hand behind the back was small and variable, with most rotations not exceeding 15 degrees. For horizontal adduction, the scapula tipped anteriorly (8 degrees +/- 3 degrees), rotated upward (5 degrees +/- 2 degrees), and rotated internally (27 degrees +/- 6 degrees). These scapular rotations provide normative data that will be useful for diagnosing scapular dysfunction.     

Comparison of robotic-assisted and conventional manual implantation of a primary total knee arthroplasty

This study was aimed to compare robotic-assisted implantation of a total knee arthroplasty with conventional manual implantation. We controlled, randomized, and reviewed 72 patients for total knee arthroplasty assigned to undergo either conventional manual implantation (excluding navigation-assisted implantation cases) of a Zimmer LPS prosthesis (Zimmer, Warsaw, Ind) (30 patients: group 1) or robotic-assisted implantation of such a prosthesis (32 patients: group 2). The femoral flexion angle (gamma angle) and tibial angle (delta angle) in the lateral x-ray of group 1 were 4.19 +/- 3.28 degrees and 89.7 +/- 1.7 degrees, and those of group 2 were 0.17 +/- 0.65 degrees and 85.5 +/- 0.92 degrees. The major complications were from improper small skin incision during a constraint attempt of minimally invasive surgery and during bulk fixation frame pins insertion. Robotic-assisted technology had definite advantages in terms of preoperative planning, accuracy of the intraoperative procedure, and postoperative follow-up, especially in the femoral flexion angle (gamma angle) and tibial flexion angle (delta angle) in the lateral x-ray, and in the femoral flexion angle (alpha angle) in the anteroposterior x-ray. But a disadvantage was the high complication rate in early stage.     

Einfluss der Muskelaktivität auf das dreidimensionale Bewegungsmuster des Schultergürtels Eine Untersuchung mittels offener MRT

The objective of this study was to analyze the influence of shoulder muscle activity on the three-dimensional motion pattern of the shoulder girdle in the living. 14 healthy volunteers were investigated with an open MRI system at 60-120 degrees abduction--with and without activity of the shoulder abductors. The 3D motion pattern of the humerus, scapula, clavicle and M. supraspinatus were computed. Under muscle activity, the glenoid demonstrated a slightly reduced elevation at 60 degrees of abduction (20.5 degrees +/- 8.2 degrees vs. 23.1 degrees +/- 6.3 degrees; not significant), and at 120 degrees a significantly higher degree of rotation under muscle activity (43.3 degrees +/- 8.6 degrees vs. 36.1 degrees +/- 5.2 degrees; p < 0.01), whereas at 90 degrees no difference was observed. This caused a significant reduction of the scapulo-humeral rhythm at 120 degrees (2.6 vs. 1.5; p < 0.01), a significant increase of the supraspinatus angle (123.3 degrees +/- 6.7 degrees vs. 117.3 degrees +/- 6.5 degrees; p < 0.05) as well as a reduction of the supraspinato-humeral relationship (1.0 vs. 0.97). The study demonstrates that muscle activity leads to an alteration of shoulder girlde motion patterns at higher degrees of abduction, with increased rotation of the scapula, an altered spatial relationship between the supraspinatus and humerus.     

Semiconstrained total elbow arthroplasty in the context of treated previous infection.

Previous infection has been considered a strict contraindication to implantation or reimplantation of an elbow prosthesis. The purpose of this study was to investigate whether these patients can in fact be successfully treated with a prosthetic arthroplasty given previous treatment of the infection. Ten consecutive prosthetic arthroplasties performed in patients with documented infections in the elbow were retrospectively reviewed. Seven of the patients had infectious complications of total elbow arthroplasties that led to resection. Two patients had previous infections from septic joints and 1 from open reduction internal fixation. The median interval of time from infection treatment to final implant was 45 months (3.8 years). All arthroplasties were performed by the same surgeon with a modified Coonrad-Morrey, semiconstrained prosthesis. Patients were monitored for clinical signs of infection including radiographic and serologic studies and clinical evaluation based on the Mayo Elbow Performance Score. Mean surveillance was 4 years (range 2.8 to 5.4 years). Eight of the 10 cases have not shown signs of infection at the latest assessment. Two have had recurrent infections. The time interval from the original infection to latest implantation did not correlate with infection recurrence. Among those 8 without recurrent infection, 7 had excellent and 1 had satisfactory results according to the Mayo Elbow Performance Score. The recurrent infections were rated as failures. The average score was 32 before and 81 after surgery. The average pain score was 15 before surgery, and the average postoperative pain score was 40. Salvage of previously infected elbows with prosthetic arthroplasty can provide excellent results in a significant proportion of patients. Although the procedure offers superior functional outcomes compared with the alternative treatment options, it is technically demanding.     

组配式假体全髋关节置换术重建双下肢等长

目的探讨股骨颈组配式假体对全髋关节置换术后双下肢等长恢复的作用及临床结果。方法本回顾性研究纳入2009年6月至2011年11月使用Neck—modular髋关节假体进行全髋关节置换术的患者共37例,所有患者对侧髋关节均存在不同原因的解剖及异常,使用常规髋关节假体难以重建双下肢等长。根据对侧下肢长度术中调整颈长,重建下肢长度。术后测量患者双侧棘踝线,测量分析影像学上肢体长度恢复情况,评估患者主观感觉及术后Harris髋关节评分。结果所有37例患者术后双侧棘踝线测量及影像学上测量双侧下肢长度偏差均≤1cm,术后12周Harris评分平均84分（63—93）,所有患者髋关节均能获得良好的活动度,无一例出现股骨髋臼撞击症（FAI）和脱位。术后平均随访14．3个月（3—32个月）,Harris评分平均94分（76～98）。结论使用股骨颈组配式髋关节假体可恢复双下肢等长,并获得良好的关节活动度,减少并发症,临床结果满意。     

三关节融合术治疗跟骨骨折远期并发症的疗效评价

目的评价采用三关节融合术治疗跟骨骨折远期并发症的临床疗效. 方法 1990年～2001年,采用距下、距舟和跟骰三关节融合术治疗12例跟骨骨折并发症患者,均行Ollier足外侧切口,其中2例行腓骨肌腱松解术,1例行胫神经减压和移位术.本组男7例,女5例,年龄29～64岁.于骨折后5～22个月,平均18个月,出现疼痛、畸形等并发症.术前后足功能评分、腓骨远端至跟骨中心距离、Bhler角、患足与正常足距骨前倾角之差和跟骨高度分别为40.00±5.22分、0.41±0.03 cm、12.00±3.40°、17.00±3.32°和4.12±0.35 cm. 结果术后获随访3～13年,平均7年.术后后足功能评分、腓骨远端至跟骨中心距离、Bhler角、患足与正常足距骨前倾角之差和跟骨高度分别为75.00±6.46分、0.73±0.02 cm、31.00±5.61°、9.00±3.15°和6.75±0.62 cm,各指标与术前比较差异均有统计学意义(P<0.05). 结论对跟骨骨折并发后足疼痛和畸形,进行病因评估及采用适当的手术方式是极其重要的;恢复后跟高度和跟骨的解剖关系是手术成功的关键.     

Contribution of monoblock and bipolar radial head prostheses to valgus stability of the elbow.

BACKGROUND: The purpose of this study was to evaluate the stabilizing effect of radial head replacement in cadaver elbows with a deficient medial collateral ligament. METHODS: Passive elbow flexion with the forearm in neutral rotation and in 80 degrees of pronation and supination was performed under valgus and varus loads (1) in intact elbows, (2) after a surgical approach (lateral epicondylar osteotomy of the distal part of the humerus), (3) after release of the anterior bundle of the medial collateral ligament, (4) after release of the anterior bundle of the medial collateral ligament and resection of the radial head, and (5) after subsequent replacement of the radial head with each of three different types of radial head prostheses (a Wright monoblock titanium implant, a KPS bipolar Vitallium [cobalt-chromium]-polyethylene implant, and a Judet bipolar Vitallium-polyethylene-Vitallium implant) in the same cadaver elbow. Total valgus elbow laxity was quantified with use of an electromagnetic tracking device. RESULTS: The mean valgus laxity changed significantly (p < 0.001) as a factor of constraint alteration. The greatest laxity was observed after release of the medial collateral ligament together with resection of the radial head (11.1 degrees +/- 5.6 degrees). Less laxity was seen following release of the medial collateral ligament alone (6.8 degrees +/- 3.4 degrees), and the least laxity was seen in the intact state (3.4 degrees +/- 1.6 degrees). Forearm rotation had a significant effect (p = 0.003) on valgus laxity throughout the range of flexion. The laxity was always greater in pronation than it was in neutral rotation or in supination. The mean valgus laxity values for the elbows with a deficient medial collateral ligament and an implant were significantly greater than those for the medial collateral ligament-deficient elbows before radial head resection (p < 0.05). The implants all performed similarly except in neutral forearm rotation, in which the elbow laxity associated with the Judet implant was significantly greater than that associated with the other two implants. CONCLUSIONS AND CLINICAL RELEVANCE: This study showed that a bipolar radial head prosthesis can be as effective as a solid monoblock prosthesis in restoring valgus stability in a medial collateral ligament-deficient elbow. However, none of the prostheses functioned as well as the native radial head, suggesting that open reduction and internal fixation to restore radial head anatomy is preferable to replacement when possible.