under the conjoined tendon. If the posterosuperior part of the rotator cuff including the teres minor was deficient, a latissimus dorsi transfer was performed with an anterior approach, and the latissimus dorsi tendon was passed under the deltoid muscle.
The cuff defect was primarily repaired, including a partial subscapularis transfer, in 14 shoulders; nine shoulders required a latissimus dorsi transfer, one required a pectoralis major transfer, and one required both a latissimus dorsi and a pectoralis major transfer.
2.2. Postoperative Treatment
An abduction pillow was used for eight weeks postoperatively. Active elevation in a sitting position from the adducted position of the shoulder was permitted after 10 weeks, and isometric cuff exercises were initiated at 12 weeks. The patients were allowed to resume heavy work after sufficient muscle strength was evident, along with range of motion (ROM) recovery, at six months or more postoperatively (Figure 3).
2.3. Clinical Evaluation
Clinical outcomes were assessed using the following criteria: ROM (active flexion, active external rotation [ER] and internal rotation [IR]); the University of California, Los Angeles shoulder score (UCLA score); the shoulder score of the Japanese Orthopaedic Association (JOA score) (Table 1); complications due to surgery.
Statistical analysis of the preoperative and postoperative data was performed using paired t-test. P values <
(a) (b)(c) (d)
Figure 2. Operative image of cuff reconstruction: (a) Two thirds of the superior aspect of the intact subscapularis and teres minor tendon has been detached subperiosteally; (b) and (c) The intact teres minor tendon has been lifted postero-superiorly while the subscapularis tendon, with a partially resected attachment site, has been lifted anterio-superiorly. The teres minor and subscapularis tendons have been side-to-side sutured and then sutured laterally to the greater tubercle; (d) If possible, the supraspinatus and infraspinatus tendons were sutured at the medial site of the transferred subscapularis and teres minor tendon.
Figure 3. The protocol of postoperative treatment.
0.05 was considered significant.
In this study, the average patient age was 64.3 years (range, 55 - 69 years) and the average follow-up period was 38.7 months (range, 24 - 72 months) (Table 2). One of the patients (Table 2, Case 3) had history of a shoulder dislocation. All patients reported none or mild shoulder pain after surgery. The mean preoperative UCLA and JOA scores were 13.1 points (range, 6 - 19) and 47.0 points (range, 13 - 79.5), respectively, and both significantly improved at the final follow-up to 28.6 points (range, 16 - 34) and 81.5 points (range, 59 - 93), respectively (P < 0.0001 for both score improvements). Active forward flexion improved from an average of 89.0˚ to
Table 1. Japanese Orthopaedic Association (JOA) score.
Table 2. All cases in the present study.
HHR: humeral head replacement; LD: latissimus dorsi transfer; PMJ: pectralis major transfer; Cofield: Subscapularis partial tendon transfer.
138.8˚ (P < 0.0004), and the ER improved from an average of 16.2˚ to 33.2˚ (P = 0.0055) postoperatively (Figure 4 and Table 3). No complications, such as dislocations, infections, fractures, or nerve injuries, were observed.
Cuff tear arthropathy was introduced in 1977 by Neer  . Numerous studies  -  of the use of total shoulder arthroplasty and HHR for this disease have been reported. However, due to concerns over loosening of the glenoid component after total shoulder arthroplasty, HHR has become the preferred treatment. In most reports on HHR  -  , complete repair of the rotator cuff was not possible; the clinical results included excellent pain relief, but only modest functional improvements.
Among the few reports describing the long-term results of HHR, Goldberg et al.   reported the surgical techniques and their long-term results for 25 shoulders at a mean of 10 years postoperatively. None of the patients reported severe pain or underwent revision surgery for problems related to the implant. In addition, 34 shoulders were also evaluated after undergoing HHR more than two years. The shoulder with complete coverage of cuff showed a trend to improved outcomes compared with the shoulders with partial coverage. Furthermore, a humeral head implant was sized by comparing with the resected humeral head fragment, and they suggested the importance of not overstuffing the joint with a larger head. Regarding the size of the humeral head implant, Pollock et al.  also suggested that some looseness of fit can be tolerated, but gross instability is unacceptable.
Figure 4. Results from the present study: (a) Active motion (flexion, external rotation); (b) UCLA score and JOA score.
Table 3. Clinical results of all cases.
ER: external rotation; IR: internal rotation; UCLA: University of California, Los Angeles; JOA: Japanese Orthopaedic Association.
As these previous reports suggested, HHR for cuff tear arthropathy can relieve pain, but cuff function is not sufficiently restored with only repair of the torn cuff muscles that have usually developed atrophy and fatty- infiltration.
Previous studies have reported the use of various operative procedures for irreparable massive rotator cuff tears, such as the patch method, the Debeyre-Patte procedure, partial repair, arthroscopic subacromial decompression, and debridement.  - At our institution, we have performed cuff reconstructions, combined with latissimus dorsi tendon and pectoralis major tendon transfers, as the primary option for irreparable massive rotator cuff tears, with the objective of restoring cuff function with healthy muscles instead of using deteriorated torn muscles. However, since some reports   have found OA progression after tendon transfer in patients with cuff tear arthropathy and an irreparable rotator cuff tear with OA, we have performed HHR using a small humeral head prosthesis in addition to cuff reconstruction.
Recently, RSA has been primarily indicated for irreparable rotator cuff tears. In many reports  -  describing RSA outcomes, good improvements in flexion have been reported, with only small improvements in ER. The present study demonstrated that HHR performed using a small humeral head and cuff reconstruction for irreparable rotator cuff tear in patients less than 70 years of age provided favorable results compared with previously reported RSA results, especially with respect to ER (Table 4). Some reports indicated that complications occured in 14% - 68% of RSA cases  - , which is a relatively high complication rate. In contrast, in the present study, dislocations, infections, fractures, nerve injuries, or other complications were not observed (Table 5).
Another advantage of our strategy is that the glenoid bone stock can be maintained after surgery. If further revision surgery is eventually required, RSA can still be considered as a reconstruction option. Since the patients included in the present study were relatively active, long-term follow-up is required to assess their continued progress.
The disadvantages of the current surgical procedure are the requirement for tendon transfers and the complicated postoperative treatment. Further follow-up is necessary to assess the long-term outcomes of the current procedure. In the present study, three patients had postoperative forward flexion of less than 90˚. These cases were Seebauer’s classification type IIA and Hamada’s classification grade 3 or 4 on the X-ray evaluations. In a future study, factors contributing to the poor results of this technique should be examined.
The small number of cases, short follow-up time and the fact that glenoid wear was not evaluated are the limitations of the present study.
Table 4. Clinical results comparing the present study and RSA.
RSA: reverse shoulder arthroplasty; Flex: flexion; ER: external rotation.
Table 5. Complications reported from RSA.
HHR using small humeral head prostheses and cuff reconstruction for irreparable massive rotator cuff tears and OA in patients less than 70 years of age showed favorable outcomes with active flexion and ER, with improvements that were greater than those reported in the previous RSA studies.
The operative procedure used in the present study is considered particularly useful in relatively young people for whom RSA is not considered to be the first option. And, with the glenoid bone stock remains, TSA or RSA can be performed as a revision surgery at a later stage.