Shoulder arthroplasty for proximal humeral malunions: long-term results

Rehabilitation following reverse total shoulder arthroplasty

Reverse or inverse total shoulder arthroplasty (rTSA) is becoming a widely accepted surgical intervention. This procedure is specifically designed for the treatment of glenohumeral (GH) joint arthritis or complex fractures, when associated with irreparable rotator cuff (RC) damage or in the presence of RC arthropathy. Additionally, rTSA is an option for the revision of a previously failed conventional total shoulder arthroplasty (TSA) or hemiarthroplasty (HA) in the RC-deficient shoulder. The physical therapist, surgeon, and patient must take into consideration that the postoperative course for a patient following rTSA should be different than the rehabilitation following a traditional TSA. rTSA has only recently been approved by the Food and Drug Administration in the United States; however, nearly a 20-year history of its use exists in Europe. To date, we are aware of no peer-reviewed published descriptions of the postoperative rehabilitation for patients having undergone this procedure. The purpose of this paper is to review the indications for rTSA, focusing on underlying pathology, and to outline a rehabilitation protocol founded on basic science principles and our experience working with patients following rTSA.

Shoulder arthroplasty for traumatic avascular necrosis: predictors of outcome

Posttraumatic avascular humeral head necrosis may require salvage shoulder arthroplasty in symptomatic cases. We tested the hypothesis that associated tuberosity malunion negatively influences the final clinical outcome after shoulder arthroplasty. Thirty-eight patients with posttraumatic avascular necrosis of the humeral head were followed clinically and radiographically for a minimum of 5 years (mean, 8 years; range, 5-13 years). To quantify preoperative tuberosity malunion, two novel radiographic parameters were introduced: on the anteroposterior view, the greater tuberosity offset as a measurement of lateralization of the greater tuberosity; and on the axillary view, the posterior offset to quantify the degree of widening at the intertubercular groove. At last followup, the average Constant and Murley score had improved from 27 points preoperatively to 57 points postoperatively; shoulder range of motion had increased from 40 degrees abduction to 116 degrees, flexion from 45 degrees to 120 degrees, and external rotation from 15 degrees to 39 degrees. Functional improvements and pain relief were substantial. A significant correlation was found between greater tuberosity offset and posterior offset and final clinical outcome. Preoperative near anatomic tuberosity alignment was associated with good results. The greater tuberosity offset and posterior offset are useful and reliable radiographic predictors of outcome.

Humeral nonunion

Humerus fractures comprise 5% to 8% of all fractures. Although uncommon, nonunions can present a frustrating challenge to the orthopedic surgeon. Various risk factors that may predispose patients to nonunion include obesity, osteoporosis, alcoholism, smoking, poor bone quality, and scar tissue. Many methods of treatment have been described with various degrees of success. The rates of healing of humeral nonunions by traditional means of internal fixation with bone graft range from 70% to 92%, although in cases of infection, poorly vascularized beds, and open, segmental, or severely comminuted fractures, secondary bony healing may still be compromised.

Early complications of operatively treated proximal humeral fractures

Minimal information exists regarding early complications after operatively treated proximal humeral fractures. Of the 82 shoulders that had osteosynthesis, 42 had a (nonmedical) complication, with 21 requiring further surgery. Of 42 shoulders with complications, 12 were related to incomplete reduction, 16 had loss of anatomic fracture fixation, 9 had delayed healing, 3 had an infection, 1 had rotator cuff failure, and 1 had loose bodies. Fixed-angle plates had lower rates of initial malpositioning and resultant malunion. Of the 22 shoulders requiring hemiarthroplasty, 14 had an early complication. Of these, 7 had complications relating to implant insertion or tuberosity malreduction at the index operation and 7 had problems with tuberosity healing. The rate of complications after operative treatment of proximal humeral fractures is high. All efforts at fracture fragment fixation with osteosynthesis and hemiarthroplasty should be directed at obtaining anatomic fracture fixation that resists displacement.

Determinants of patient satisfaction with outcome after shoulder arthroplasty

The purpose of this investigation was to identify the determinants of patient satisfaction with outcome after hemiarthroplasty and total shoulder arthroplasty. Seventy patients who underwent shoulder arthroplasty were studied to determine predictors of patient satisfaction. Patient satisfaction was graded on an ordinal scale from 1 to 10. There was a significant association between patient satisfaction and age (P = .010) and between patient satisfaction and worker's compensation status (P = .018). There was no significant decrease in patient satisfaction for patients with rotator cuff tears. Patient satisfaction was significantly associated with all pain and function variables at follow-up (P < .05). The American Shoulder and Elbow Surgeons score was significantly correlated with patient satisfaction (P = 0.680, P < .05). Independent predictors of satisfaction included pain with activities of daily living, painless use of the arm above the shoulder, and difficulty with toileting (R(2) = 0.555). Subjective variables associated with pain were independent predictors of patient satisfaction. Thus, in assessing patient satisfaction after shoulder arthroplasty, we emphasize the importance of patient-derived subjective assessment of symptoms and function.

The results of arthroplasty in osteoarthritis of the shoulder

We have undertaken a prospective clinical and radiological analysis of 124 shoulder arthroplasties (113 patients) carried out for osteoarthritis. The clinical results showed improvement in the absolute Constant score and the American Shoulder and Elbow Surgeons score of 22 and 43, respectively. Both were statistically significant (p < 0.001). There was no significant difference in the scores after hemiarthroplasty and total arthroplasty in those patients with an intact rotator cuff. When revision was used as the end-point for survival at ten years, survival of 86%, or 90% if glenoid components made of Hylamer sterilised in air were omitted, was obtained in primary osteoarthritis. The most common cause for revision in the hemiarthroplasty group was glenoid pain at a mean of 1.5 years; in the total arthroplasty group it was loosening of the glenoid at a mean of 4.5 years. Analysis of pre-operative factors showed that the risk of gross loosening of the glenoid increased threefold when there was evidence of erosion of the glenoid at operation. Shoulder arthroplasty should not be delayed once symptomatic osteoarthritis has been established and should be undertaken before failure of the cuff or erosion of the glenoid are present.

Proximal humerus fracture sequelae: impact of a new radiographic classification on arthroplasty

Our goal was to analyze the results of unconstrained shoulder replacement in a large series of sequelae of proximal humeral fractures in order to validate a previously described surgical classification. In a multicenter study, we retrospectively evaluated 203 patients with sequelae of proximal humeral fractures who were treated with a nonconstrained modular and adaptable prosthesis. The mean followup was 42 months (range, 24-96 months). We identified 137 impacted fractures with humeral head collapse or necrosis (Type 1 sequelae), 25 unreducible dislocations or fracture-dislocations (Type 2), 22 nonunions of the surgical neck (Type 3), and 19 severe tuberosity malunions (Type 4). Results of nonconstrained shoulder arthroplasty for the treatment of Type 1 and Type 2 sequelae were predictably good because no greater tuberosity osteotomy was performed. The distorted anatomy was accepted, and both the prosthesis and technique were modified accordingly. Total shoulder arthroplasty yielded better results than hemiarthroplasty. Patients with Type 3 or Type 4 sequelae had poor functional results with nonconstrained arthroplasty because greater tuberosity osteotomy was needed. This study validates our fracture sequelae classification. We no longer use unconstrained prostheses in Type 3 and Type 4 fracture sequelae and propose peg bone grafting or low-profile fracture prosthesis for patients with Type 3 sequelae and reverse arthroplasty for those with Type 4 sequelae.

LEVEL OF EVIDENCE

Prognostic study, level IV (case series). See Guidelines for Authors for a complete description of levels of evidence.

Rehabilitation following total shoulder arthroplasty

Total shoulder arthroplasty (TSA) is a standard operative treatment for a variety of disorders of the glenohumeral joint. Patients, who have continued shoulder pain and loss of function in the presence of advanced joint pathology, despite conservative management, are often managed by undergoing a TSA. The overall outcomes that are reported after surgical intervention are quite good and appear to be primarily determined by the underlying pathology and the tissue quality of the rotator cuff. The current Neer protocol for postoperative TSA rehabilitation is widely used and based on tradition and the basic science of soft tissue and bone healing. The purpose of this paper is to review the indications for TSA, focusing on the underlying pathologies, and to describe the variables that impact the rehabilitation program of individuals who have had a TSA. A postoperative TSA rehabilitation protocol and algorithm, founded on basic science principles and tailored toward the specific clinical condition, are presented.

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.