Total shoulder arthroplasty with a tissue-ingrowth glenoid component

A newly designed, uncemented, tissue-ingrowth glenoid component with a porous surface was used in association with the Neer humeral head prosthesis for 32 total shoulder arthroplasties in 29 patients. The diagnoses for the shoulders were osteoarthritis in 17, rheumatoid arthritis in eight, and traumatic arthritis in seven. Follow-up evaluations averaged 51 months (range, 29 to 80 months). Five complications occurred, necessitating four reoperations: two for glenoid component dissociation, one for humeral loosening, and one for infection. Little or no pain was experienced after the operation in 27 (96%) of the 28 shoulders that required no additional surgery. Average active abduction was 145°, average external rotation was 59°, and median internal rotation was to 112. Three glenoid components had probable loosening on radiographic examination. Eight shoulders had some degree of instability; a complication related to the glenoid component (polyethylene dissociation) or probable loosening not yet requiring reoperation developed in four of these (p < 0.02). These data support the continuing use of an uncemented, tissue-ingrowth glenoid component in arthritic shoulders with adequate bone support. Joint instability must be avoided to lessen complications and the need for revision surgery.     

Total shoulder arthroplasty versus hemiarthroplasty. Indications for glenoid resurfacing

The results of total shoulder arthroplasty and hemiarthroplasty in a similar patient population were compared in an effort to define more clearly the indications for resurfacing the glenoid. The results of 64 Neer hemiarthroplasties in 59 patients were compared with 146 Neer total shoulder arthroplasties in 134 patients in a retrospective review of the period between 1974 and 1986. The average follow-up period was 44 months (range, 24-124 months). Hemiarthroplasty and total shoulder arthroplasty produced similar results in terms of functional improvement. Pain relief, range of motion, and patient satisfaction were better with total shoulder arthroplasty than hemiarthroplasty in the rheumatoid population. Progressive glenoid loosening was found in 12% of total should arthroplasties but no correlation with pain relief or range of motion was noted. Total shoulder arthroplasty is recommended for patients with inflammatory arthropathies, and hemiarthroplasty is recommended for patients with osteoarthritis, avascular necrosis, and four-part fractures with preservation of glenoid congruity and absent synovitis.     

Total shoulder arthroplasty does not correct the orientation of the eroded glenoid

Background and purpose Alignment of the glenoid component with the scapula during total shoulder arthroplasty (TSA) is challenging due to glenoid erosion and lack of both bone stock and guiding landmarks. We determined the extent to which the implant position is governed by the preoperative erosion of the glenoid. Also, we investigated whether excessive erosion of the glenoid is associated with perforation of the glenoid vault.

Methods We used preoperative and postoperative CT scans of 29 TSAs to assess version, inclination, rotation, and offset of the glenoid relative to the scapula plane. The position of the implant keel within the glenoid vault was classified into three types: centrally positioned, component touching vault cortex, and perforation of the cortex.

Results Preoperative glenoid erosion was statistically significantly linked to the postoperative placement of the implant regarding all position parameters. Retroversion of the eroded glenoid was on average 10° (SD10) and retroversion of the implant after surgery was 7° (SD11). The implant keel was centered within the vault in 7 of 29 patients and the glenoid vault was perforated in 5 patients. Anterior cortex perforation was most frequent and was associated with severe preoperative posterior erosion, causing implant retroversion.

Interpretation The position of the glenoid component reflected the preoperative erosion and “correction” was not a characteristic of the reconstructive surgery. Severe erosion appears to be linked to vault perforation. If malalignment and perforation are associated with loosening, our results suggest reorientation of the implant relative to the eroded surface.     

Total shoulder arthroplasty does not correct the orientation of the eroded glenoid

Background and purpose

Alignment of the glenoid component with the scapula during total shoulder arthroplasty (TSA) is challenging due to glenoid erosion and lack of both bone stock and guiding landmarks. We determined the extent to which the implant position is governed by the preoperative erosion of the glenoid. Also, we investigated whether excessive erosion of the glenoid is associated with perforation of the glenoid vault.

Methods

We used preoperative and postoperative CT scans of 29 TSAs to assess version, inclination, rotation, and offset of the glenoid relative to the scapula plane. The position of the implant keel within the glenoid vault was classified into three types: centrally positioned, component touching vault cortex, and perforation of the cortex.

Results

Preoperative glenoid erosion was statistically significantly linked to the postoperative placement of the implant regarding all position parameters. Retroversion of the eroded glenoid was on average 10° (SD10) and retroversion of the implant after surgery was 7° (SD11). The implant keel was centered within the vault in 7 of 29 patients and the glenoid vault was perforated in 5 patients. Anterior cortex perforation was most frequent and was associated with severe preoperative posterior erosion, causing implant retroversion.

Interpretation

The position of the glenoid component reflected the preoperative erosion and “correction” was not a characteristic of the reconstructive surgery. Severe erosion appears to be linked to vault perforation. If malalignment and perforation are associated with loosening, our results suggest reorientation of the implant relative to the eroded surface.Based on 2,540 shoulder arthroplasties, Bohsali et al. (2006) reported the aseptic loosening rate to be 39%. Many other studies have shown that implant malalignment may cause high radiographic loosening rates (Franklin et al. 1988, Nyffeler et al. 2003, Farron et al. 2006, Habermeyer et al. 2006, Hopkins et al. 2007, Shapiro et al. 2007).Glenoid implant positioning is a challenging procedure. Reasons include poor intraoperative glenoid exposure, lack of reference landmarks, and the surgeon being (mis)guided by the orientation of the eroded glenoid surface. Friedman et al. (1992) and Walch et al. (1999) found that due to osteoarthritic erosions, the preoperative glenoid was retroverted by more than 10°. Walch et al. (1999) observed that in 24% of total shoulder arthroplasties (TSAs) the preoperative retroversion was excessive due to arthritic changes showing on average 23° of retroversion. It seems likely that such deformed glenoid bone will cause malpositioning of glenoid implants. A particular consequence of this is that erosion may lead to an implant position that perforates the glenoid vault (Yian et al. 2005).In anatomical studies, normal glenoid version has been found to vary within a range of about 20°, with an average retroversion of 1–2° (Churchill et al. 2001, Kwon et al. 2005, Codsi et al. 2008). Without knowing the patient native version, the aim of TSA is to position the prosthesis in a neutral orientation, correcting for pre-existing erosion of the glenoid when possible.We hypothesized that in routine surgical practice, the position of the implant is determined by the preoperative orientation of the glenoid and surgery does not achieve neutral positioning. A second hypothesis was that excessive erosion of the glenoid would be associated with perforation of the glenoid vault by the implant, which may have important implications for the success of the arthroplasty.     

Total shoulder arthroplasty

Seventy Neer Series II total shoulder arthroplasties were performed in 65 patients. The average age was 69 years. The average follow-up period was 40 months. Rheumatoid arthritis or osteoarthritis was the diagnosis in 34 and 29 shoulders, respectively. Rotator cuff tears were identified in 18 patients. There were no infections, neurological injuries, or vascular injuries, or vascular injuries. Two glenoid fractures and two humeral shaft fractures were sustained intraoperatively. Uniformly, excellent pain relief was obtained regardless of the disease process. The resultant average increase in range of motion (ROM) was 60 degrees of active forward elevation and 18 degree of external rotation. Radiolucent lines were present in 17 humeral components; however, none was symptomatic or had progressed in thickness. Five glenoid components demonstrated progression of radiolucency, and two required revision. Both of these were in patients with rheumatoid arthritis. Although pain relief was uniformly good among all patient groups, a statistically significant degree of improvement in ROM was found in individuals with osteoarthritis. The etiology of the disease process and the status of the rotator cuff may determine the eventual outcome in individuals treated with total shoulder arthroplasty.     

Retroverted glenoid reconstruction using glenoid plate in reverse shoulder arthroplasty

Purpose

The objective of this study is to evaluate the clinical and radiological results of reverse shoulder arthroplasty (RSA) with glenoid plating in a consecutive series of patients affected by cuff tear glenohumeral arthropathy with glenoid retroversion >15°. We hypothesized that autologous humeral head graft may be better stabilized between the baseplate and the native glenoid surface with the use of a glenoid plate.

Methods

Twenty consecutive patients affected by cuff tear arthropathy with glenoid retroversion >15° (B2 or C according to Walch classification) were enrolled in this study. To reconstruct the glenoid, a dedicated plate was used in addition to the standard reverse shoulder baseplate and the glenosphere. Clinical and radiological assessment was performed using constant score (CS), subjective shoulder value (SSV), X-rays and CT scan at 6, 12 and 24 months of follow-up. Healing and resorption of the graft and detection of the glenoid version were assessed.

Results

Sixteen patients were available for final follow-up. The mean preoperative retroversion of the glenoid was 24°, while the post-op was 2° (p = 0.002). At 24 months of follow-up, mean CS and SSV were 61 and 70. Respect to preoperative scores, the results were statistically significant (p < 0.001). The last CT scan revealed: a complete healing of the graft in 100% of cases; graft resorption less than 25% in two patients (12.5%); glenoid retroversion of 4°. A negative statistically significant correlation was found between final CS and preoperative glenoid retroversion (0.039).

Conclusions

The present study reports the favorable outcomes of retroverted glenoid reconstruction with glenoid plates in RSA, an alternative method to address severe glenoid deficiency.

Level of evidence

Level IV, case series with no comparison group.

     

Total shoulder arthroplasty

A prospective study was done of fifty total shoulder replacements in forty-four patients who were followed for an average of 3.5 years (range, 2.0 to 7.5 years). The preoperative diagnosis was osteoarthritis in thirty-three shoulders, rheumatoid arthritis in eleven, and a previous fracture of the humeral head in six shoulders. Nine of the shoulders had a tear of the rotator cuff. The Neer-II system of total shoulder replacement with a non-metal-backed component was used in all fifty shoulders. At follow-up, forty-four shoulders (88 per cent) had no significant pain. Of the six painful shoulders, four had loosening of the glenoid component and one had malposition of both components. Three of the six shoulders had no significant pain after revision. The average range of active forward elevation in all of the shoulders improved from 71 to 100 degrees, and both external and internal rotation improved as well. Five specific activities of daily living were evaluated, and the patients' ability to perform them improved from 14 to 78 per cent. Thirty-five shoulders (68 per cent) were rated by the patients as much better; thirteen shoulders (26 per cent), as better; and three (6 per cent), as no better. An incomplete lucent line was noted around five (10 per cent) of the cemented humeral stems and around thirty-seven (74 per cent) of the glenoid prostheses. Four arthroplasties (8 per cent) required revision: three for loosening of the glenoid component and one for malposition of both components.(ABSTRACT TRUNCATED AT 250 WORDS)     

Revision shoulder arthroplasty for glenoid component loosening

Although glenoid component loosening has been recognized as a common reason for failure after total shoulder arthroplasty, there are few studies on the outcome of revision surgery for this problem. The purpose of this study is to determine the outcome of patients who underwent revision for glenoid component loosening. Between 1976 and 2002, 68 shoulders in 66 patients underwent revision for glenoid loosening at our institution. Group I consisted of 33 shoulders that underwent placement of a new glenoid component, and group II consisted of 35 shoulders that had removal and bone grafting without glenoid reimplantation. Follow-up averaged 3.8 years for group I and 6.2 years for group II. There was significant overall improvement in pain from preoperatively to postoperatively in both groups (P = .0001). Pain relief occurred in 23 of 33 shoulders in group I and in 24 of 35 in group II (P = .9203). Regarding range of motion, there was no significant change from preoperatively to postoperatively (P > .05), except for active elevation in group I (P = .0387). Patient satisfaction occurred in 24 in group I and in 19 in group II (P = .1150). The rate of survival free of reoperation at 5 years was 91% (95% confidence interval, 81% to 100%) in group I and 78% (95% confidence interval, 63% to 96%) in group II (P = .3019). When the Neer result rating was applied, 9 shoulders in group I and 3 in group II had an excellent or satisfactory result (P = .0432). Twenty shoulders had late positive cultures, most commonly, Propionibacterium acnes. Glenoid revision surgery will often lead to pain relief and patient satisfaction. There is a slight clinical benefit to reimplanting a glenoid component whenever structurally possible. Positive cultures in revision surgery are common, with uncertain clinical significance.