Influence of arm lengthening in reverse shoulder arthroplasty

Evaluation of lengthening in reverse shoulder arthroplasty comparing X-rays and computerised tomography

“…In our patients, arm lengthening averaged 1.9 cm on the radiographic measurements using an onlay reverse shoulder arthoplasty, which is consistent with the previously published literature with Grammont's design [18,19]. In contrast, measurements on CT scans demonstrated a greater amount of arm lengthening (2.8 cm).…”

“…Lädermann reported an average humeral lengthening of 0.2 cm with Grammont's design [6,19]. Humeral shortening was related to dislocations in their cohort [6] but did not affect functional outcome [19]. We did not find a correlation between humeral shortening and dislocation on both imaging techniques in our patients.…”

“…Lädermann reported an average humeral lengthening of 0.2 cm with Grammont's design [6,19]. Humeral shortening was related to dislocations in their cohort [6] but did not affect functional outcome [19].…”

“…Yet, these criteria are subjective and depend on soft-tissue impairment as well as patient relaxation. Objective techniques for postoperative assessment of deltoid tension include evaluation of the acromio-epiphyseal distance compared to the contralateral humerus [9] the difference in pre-and postoperative acromio-metaphyseal distance corrected for abduction of the arm in revision arthroplasty [16], the difference of pre-and postoperative deltoid length with respect to the greater tuberosity [17] as well as bilateral scaled radiographs of the humerus [6,18,19]. The lack of bony landmarks in case of malunion or resorption of the greater tuberosity as well as extended humeral bone defects justifies the use of the contralateral side for pre-operative planning [6] as well as postoperative assessment of lengthening.…”

Improvement of the shoulder function after large segment resection of the proximal humerus with the use of an inverse tumour prosthesis

“…A short arm lengthening from 0 to 2 cm seems to be favourable to gain a sufficient pretension of the deltoid muscle to achieve a better functional outcome and to avoid dislocation as Lädermann et al presented. However, a misjudgment of the correct reconstruction length, particularly an arm overlength, may cause neurological lesions [28,29] with a negative influence on the shoulder function. The IPHP used in our series allowed the adaption of the implant length in 2-cm steps only, which may lead to an insufficient pretension of the musculature with a consecutive joint instability and implant dislocation as seen in 4/17 patients.…”