Reconstruction of humeral length and centering of the prosthetic head in hemiarthroplasty for proximal humeral fractures

Anatomic reconstruction of humeral length in hemiarthroplasty for complex proximal humeral fractures is difficult because reliable surgical landmarks are missing or are destroyed by the fracture. The pectoralis major tendon is a reliable landmark to determine prosthetic height intraoperatively. This study analyzed the clinical outcome, reconstruction of humeral length, centering of the prosthetic head in the glenoid, and tuberosity positioning and healing, using the pectoralis major tendon as a reference intraoperatively. The study included 30 patients. In 21 patients (group 1), humeral length reconstruction was performed using the pectoralis major tendon as a reference; in 9 (group 2), this reference was not used. Patients underwent a clinical and radiologic evaluation at a mean of 22.7 months. Group 1 showed significantly better results in clinical and radiologic values, especially in anatomic reconstruction of humeral length, than group 2. Clinical outcome depended significantly on greater tuberosity healing and centering of the prosthetic head in the glenoid.     

Shoulder hemiarthroplasty in the management of humeral head fractures

The results of hemiarthroplasty for shoulder fracture were evaluated in 26 patients, 20 women and 6 men with a mean age of 64.7 +/- 8.2 years. The follow-up period was 2 to 7 years. Cofield prostheses were used for the first 10 patients and subsequently 9 Global and 7 Aequalis prostheses were implanted, all cemented. The clinical outcome was assessed using the Constant-Murley scale. The mean score, at the last follow-up, was 70.4 +/- 16.4 (39-96). Mean forward elevation of the arm was 150 degrees (300-175 degrees), mean abduction was 145 degrees (30 degrees -170 degrees), and mean external rotation was 30 degrees (10 degrees-45 degrees). In most of the cases internal rotation corresponded with a position of the dorsum of the hand at the L3 vertebrae. The patients in our series achieved their optimal clinical result within the first 6 months after operation. Shoulder hemiarthroplasty is a worthwhile procedure, giving predictable results provided the patients have been carefully selected, the individual anatomy of the shoulder is restored and an aggressive rehabilitation program is implemented during the first six months after surgery.     

肱骨头置换治疗老年人肱骨头粉碎性骨折

目的探讨人工肱骨头置换治疗老年人肱骨头粉碎性骨折的疗效。方法对13例肱骨头粉碎性骨折老年患者（〉75岁）均采用骨水泥型柄的非限制性人工肱骨头置换术。结果13例均获随访,时间3～25（12±4．5）个月。3例基本达到骨折前的状况,10例生活基本自理。结论人工肱骨头置换治疗肱骨头粉碎性骨折老年患者,可早期进行功能锻炼,减少并发症,改善生活质量,疗效满意。     

Surgical landmarks to determine humeral head retrotorsion for hemiarthroplasty in fractures

Malrotation has been suggested as a cause of failure of hemiarthroplasty of the proximal humerus. Placing a shoulder prosthesis in relationship to the bicipital groove might reproduce individual anatomy more reliably than using a standardized retrotorsion. The purpose of this study was to determine criteria for accurate adjustment of retrotorsion even when the proximal bicipital groove is destroyed, as is the case in fractures. The distance of the humeral head equatorial plane to the center of the bicipital groove was measured by high-resolution computed tomography at 4 levels (proximal and distal with 2 intermediate levels). The distal distance was considered to correspond to available references in fracture cases. The mean proximal distance was 8.0 mm (10th percentile, 6.2 mm; 90th percentile, 9.8 mm), and the mean distal distance was 8.5 mm (10th percentile, 7.1 mm; 90th percentile, 9.9 mm). As to the clinical relevance, there was no statistically significant difference between distances. For practical purposes in fracture indications, it is adequate to adjust the retrotorsion of the prosthetic component to the distal bicipital groove.     

The pectoralis major tendon as a reference for restoring humeral length and retroversion with hemiarthroplasty for fracture

The success of anatomic reattachment of the tuberosities in proximal humeral fractures, treated with hemiarthroplasty, correlates with functional results. The purpose of this study was to determine the value of the upper edge of the pectoralis major insertion (PMI) as a landmark to establish the proper height and version of hemiarthroplasty implanted for proximal humeral fractures. Twenty cadaveric humeri were studied by CT scan to analyze the relationship between the PMI and humeral height and retroversion. The mean distance from the PMI to the tangent to the humeral head was 5.64 cm. The mean distance of the PMI to the posterior fin of the prosthesis was 1.06 cm. The mean angle between the PMI and the posterior fin of the prosthesis was 24.65 degrees. The upper edge of the pectoralis major insertion constitutes a reproducible reference point to restore proper humeral height and retroversion in hemiarthroplasty for proximal humeral fracture.     

Variations in the retroversion of the humeral head

It is generally accepted that the humeral head in adults is retroverted between 25 degrees and 35 degrees. To assess the validity of this belief, 336 dry bone specimens of humeral heads were measured. The specimens were taken from various ethnic groups: white Americans, black Americans, New Mexican Indians, northern Chinese, Alaskan Eskimos, and Negev Desert bedouins. There was significant variation in retroversion angle between specimens from different ethnic groups and even wider variation between specimens within particular groups--a finding contrary to popular belief. Retroversion angle in the specimens ranged from -8 degrees to +74 degrees. In addition, 50 fetal skeletons of white and black Americans were studied. The mean humeral head retroversion angle in the fetal skeletons was 78 degrees, much greater than that in adults. It was evident that the large retroversion angle in the very young decreases with growth and that it does so to a varying extent among different ethnic groups and individuals. It is of clinical importance to understand the variations in humeral head retroversion among individuals undergoing operation and the ways in which this parameter might be manipulated to surgical advantage.     

The development of humeral head retroversion

Humeral head retroversion is important in a variety of clinical situations, but it is not known when retroversion actually develops to adult values. In utero and at birth, the humeral head is known to be in marked retroversion. It derotates sometime thereafter to assume the more standard value with which orthopedic surgeons are familiar. By studying a unique collection of children's bones (180 humeri), I have been able to determine that the greater part of this process takes place, on average, by the age of 8 years (SD +/- 2.12 years); from then on, however, the development continues more slowly until the final adult dimensions are reached, as heralded by the appearance of the radial groove at approximately 16 years of age. This process, along with its timing, appears to be similar, but opposite in direction to, the derotation process that is known to take place in the hip. It has not previously been documented in the shoulder.     

Outcome of cemented Neer II hemiarthroplasty in displaced humeral head fractures

The functional and radiological outcome of cemented Neer II hemiarthroplasty performed within six weeks after a fracture-dislocation or a three/four-part humeral head fracture was evaluated in 48 patients with an average age of 73 years (range: 45 to 89), with an average follow-up period of 44 months (range: 6 to 106). Thirty-two (67%) patients were satisfied or very satisfied. Twenty-nine (61%) patients had no or mild pain, 17 (35%) had moderate pain and two (4%) had severe pain. Constant Score averaged 49 (range: 8 to 71) compared to 78 (range: 40 to 100) for the nonoperated shoulder (p < 0.001). The 26 (57%) patients with abnormal radiographs (malpositioning or loosening of the prosthesis, non-union of tuberosities, heterotopic ossification, and/or glenoid erosion) had a significantly lower Constant Score (45 [range: 8 to 69] versus 55 [range: 31 to 71], p = 0.013). The functional outcome is disappointing and related to the radiographic status. The patients however seem to be satisfied despite a rather stiff shoulder and in our opinion a non-acceptable pain relief.     

Inlay hemiarthroplasty of the humeral head for nontraumatic osteonecrosis

BackgroundOsteonecrosis of the humeral head often occurs in younger individuals and presents a difficult clinical situation. The purpose of this study was to evaluate the patient reported outcomes in patients undergoing inlay hemiarthroplasty for nontraumatic osteonecrosis of the humeral head. We hypothesized that patients would achieve a meaningful clinical improvement.MethodsA retrospective review of prospectively collected data on 9 patients undergoing inlay hemiarthroplasty for humeral head osteonecrosis was conducted. The American Shoulder and Elbow Surgeons Shoulder score (ASES), Simple Shoulder Test (SST), visual analog scale for pain (VAS), and range of motion measurements were collected preoperatively and at final follow-up. Radiographs were evaluated for any evidence of component loosening or glenoid wear. The primary outcome was achievement of substantial clinical benefit (SCB) for ASES.ResultsPostoperatively at a mean of 7.2 years the ASES improved from 35 to 73 (p = 0.011), the SST improved from 2 to 6 (p = 0.038), and the VAS for pain decreased from 7 to 3 (p = 0.009). Forward elevation increased from 96° to 138° (p = 0.012) and external rotation increased from 13° to 63° (p = 0.007). SCB for ASES was seen in 7 out of the 9 patients (78%). Asymptomatic mild or moderate glenoid wear was seen in 4/9 (44%) of patients. One patient (11%) developed symptomatic glenoid wear necessitating conversion to total shoulder arthroplasty.ConclusionInlay hemiarthroplasty offers a viable solution to osteonecrosis of the humeral head.Level of Evidence: Level IV; Treatment Study     

Primary hemiarthroplasty for treatment of proximal humeral fractures

BACKGROUND: Primary hemiarthroplasty of the shoulder is used to treat complex proximal humeral fractures, although the reported functional results following this method of treatment have varied widely. The aim of this study was to prospectively assess the prosthetic survival and functional outcomes in a large series of patients treated with shoulder hemiarthroplasty for a proximal humeral fracture. By determining the factors that affected the outcome, we also aimed to produce models that could be used clinically to estimate the functional outcome at one year following surgery. METHODS: A thirteen-year observational cohort study of 163 consecutive patients treated with hemiarthroplasty for a proximal humeral fracture was performed. Twenty-five patients died or were lost to follow-up in the first year after treatment, leaving 138 patients who had assessment of shoulder function with use of the modified Constant score at one year postinjury. RESULTS: The overall rate of prosthetic survival was 96.9% at one year, 95.3% at five years, and 93.9% at ten years. The overall median modified Constant score was 64 points at one year, with a typically good score for pain relief (median, 15 points) and poorer scores, with a greater scatter of values, for function (median, 12 points), range of motion (median, 24 points), and muscle power (median, 14 points). Of the factors that were assessed immediately after the injury, only patient age, the presence of a neurological deficit, tobacco usage, and alcohol consumption were significantly predictive of the one-year Constant score (p < 0.05). Of the factors that were assessed at six weeks postinjury, those that predicted the one-year Constant score included the age of the patient, the presence of a persistent neurological deficit, the need for an early reoperation, the degree of displacement of the prosthetic head from the central axis of the glenoid seen radiographically, and the degree of displacement of the tuberosities seen radiographically. CONCLUSIONS: Primary shoulder hemiarthroplasty performed for the treatment of a proximal humeral fracture in medically fit and cooperative adults is associated with satisfactory prosthetic survival at an average of 6.3 years. Although the shoulder is usually free of pain following this procedure, the overall functional result, in terms of range of motion, function, and power, at one year varies. A good functional outcome can be anticipated for a younger individual who has no preoperative neurological deficit, no postoperative complications, and a satisfactory radiographic appearance of the shoulder at six weeks. The results are poorer in the larger group of elderly patients who undergo this procedure, especially if they have a neurological deficit, a postoperative complication requiring a reoperation, or an eccentrically located prosthesis with retracted tuberosities.     

Treatment of fractures of the humeral head by cemented and cementless hemiarthroplasty. Our experience

Patients submitted to shoulder hemiarthroplasty for the treatment of fracture of the humeral head were analyzed. The study was conducted from 1991 to June 2001 using 2 different prosthetic models: the Neer cemented prosthesis and the Randelli cementless prosthesis. The authors were able to evaluate 93 cases out of 148 operated on. A review of data revealed the essential importance of reconstruction of the tuberosity and rehabilitation. It was also observed that the age of the patient and the severity of the fracture did not in any way influence results. X-ray examinations did not shed light on loosening phenomena in prosthetic implants. Erosion of the glenoid was observed only when two factors coexisted: incorrect position of the prosthesis and low mobility of the shoulder. The study allowed us to reveal numerous prognostic elements, both favorable and adverse, and to measure their importance and priority.     

Shoulder hemiarthroplasty for the treatment of complex proximal humeral fractures

Objective: To investigate the indication, perioperative announcements, selection of prosthesis and clinical results of shoulder hemiarthroplasty for the treatment of complex proximal humeral fractures.Methods: A total of 55 patients who suffered from com-plex proximal humeral fractures were treated by shoulder hemiarthroplasty. The mean age was 55.6 years and mean follow-up period was 25.1 months. The scoring system modi-fication for hemiarthroplasty (SSMH) had been adopted for evaluation at the latest follow-up.Results: The pain was obviously relieved in all patients. Fifty patients were painless and 5 patients had slight pain. The mean range of motion was 100°(90°-110°) in abduction, 95°(80°-100°) in forward flexion, 35°(30°-40°) in extemal rotation and internal rotation was confined at L2 level (L1-L3). The mean SSMH score was 27.9 (24-29). Fifty patients (90.1%) were satisfied with the clinical outcome.Conclusions: Shoulder hemiarthroplasty is an effective method to treat complex proximal humeral fractures. The proper selection of patients and prosthesis, good operation skill and enough functional exercise are the key points of successful treatment.     

人工肱骨头置换治疗肱骨近端三、四部分骨折

目的探讨人工肱骨头置换治疗肱骨近端骨折,术中应注意的关键问题. 方法采用Thompson入路行人工肱骨头置换术23例. 术后随访6～36个月,平均随访21.1个月.用ASES评分对患肩进行术后功能评估.结果医师客观评定:全部患者肩关节活动明显改善,肌力恢复良好,肩关节稳定,5例轻压痛,1例发生撞击.患者主观评定:疼痛平均102分,肩关节稳定平均106分,完成10个日常生活动作22例,完成7个日常生活动作1例.复查X线片显示人工肱骨头位置良好,无假体松动,肱骨大、小结节骨折愈合. 结论术中肩周软组织保护及修复,人工肱骨头假体安装和肱骨大、小结节解剖重建是提高人工肱骨头置换术疗效的关键技术.     

肱骨近端骨折肩关节置换术假体高度确定的解剖学研究

目的 探讨肱骨近端骨折肩关节置换术中确定假体植入高度的方法.方法 选择成人尸体标本11具,男7具,女4具,共22个肩关节.测量胸大肌肱骨止点上缘至肱骨头关节面顶点的距离(PMT)、大结节高度(HT)及肱骨长度(HL),计算PMT/HL. 结果 所有标本PMT平均为(5.10±0.54)cm,HT平均为(0.78±0.19)cm,HL平均为(28.9±1.9)cm,PMT/HL的平均值为17.6%.所有标本HL的测量结果均乘以17.6%,分别与其PMT的测量结果比较偏差不超过0.5 cm.PMT、HT、HL左侧和右侧的测量结果差异均无统计学意义(P＞0.05).PMT和HL的测量结果呈正相关,HT和HL的测量结果无明显相关性. 结论 胸大肌腱止点上缘可作为肱骨近端骨折肩关节置换术中确定假体植入高度的可靠参照.术中可以根据国人PMT的平均值5.10 cm或个体化的数值,即将测量的术前健侧HL乘以固定的系数17.6%来推测患侧PMT,从而决定假体顶点至胸大肌腱肱骨止点上缘的距离.     

肱骨近端骨折反置式人工全肩关节置换术与人工肱骨头置换术的比较

SummaryEarly evidence from two small retrospective cohort studies suggests that reverse shoulder arthroplasty appears similar to hemiarthroplasty for the treatment of proximal humeral fractures in an elderly population.One study found no significant differences for either functional outcomes or range of motion at follow-up.The other study found that Constant scores and range of motion may be better for reverse shoulder arthroplasty.However,only retrospective cohort studies were available,so no definitive conclusions can be drawn from these two small 2项小样本回顾性队列研究的结论认为,反置式人工全肩关节置换术(RSA)与人工肱骨头置换术(HA)在治疗老年性肱骨近端骨折方面疗效相当.其中1项研究发现,随访期间两种方法在功能恢复和活动范围改善方面无明显统计学差异.另1项研究则认为经过RSA治疗的患者,Constant肩部评分结果和肩部活动范围的改善要更好.但是,目前的研究结果来自于回顾性队列研究,因此并不能从中得出比较确切的结论.     

Measurement of the humeral head retroversion angle. A new radiographic method

BACKGROUND: In this study, a simple and reliable radiographic method is described to determine the torsional profile of the humeral head. METHODS: First, by using a specially developed frame, the humeral head retroversion angles (HRAs) of 20 dry humeri were measured by an anatomist and an orthopedist. Then the HRA of these humeri were measured by two orthopedists on radiographs taken in semi-axial view when the humeri were in 20 degrees abduction. RESULTS: The results were assessed with the SPSS 9.05 program, and the repeatability coefficient of both methods was 98%. The average difference in angle determination between the two methods was 0.9 degrees; the maximum difference was 3 degrees. After that, posteroanterior semi-axial radiographs of both humerus bones of 40 healthy volunteers were taken by positioning their arms in 20 degrees abduction to the X-ray axis. The mean HRA difference between the right and left sides was 0.4 degrees (maximum difference 3 degrees ) and is of no clinical significance. It was determined that left and right HRAs can be taken as a reference to each other. For measurement of the HRA in the planning of proximal humeral rotation osteotomy and prosthesis replacement arthroplasty, the presented radiographic method can be used with a high rate of accuracy.