BACKGROUND: Although humeral shortening as a sequel of septic arthritis of the shoulder in infants has been reported in previous studies, functional disorders of the shoulder resulting from humeral shortening have not yet been clarified. In this study, we retrospectively investigated the long-term outcome of septic arthritis of the shoulder in neonates and infants and examined the relationship between growth disturbance of the humerus and decreased range of motion with respect to glenohumeral joint laxity. METHODS: We reviewed the cases of fifteen patients (sixteen shoulders) with an age of a few days to 2.6 years at the onset of the disease who were followed from 5.0 to 17.9 years. We noted the initial treatment method and evaluated humeral length and shoulder function at the time of the final follow-up. For the final treatment results, we classified the shoulders with normal findings on radiographs as Grade I, those with humeral head deformity as Grade II, and those with humeral head deformity with inferior subluxation as Grade III. RESULTS: Primary treatment included arthrotomy in ten shoulders. The delay between the onset of the disease and surgery ranged from three to twenty-six days. At the time of the final follow-up, the results were Grade I in five shoulders, Grade II in six shoulders, and Grade III in five shoulders. The mean humeral shortening was 0.1 cm for Grade-I shoulders, 0.9 cm for Grade-II shoulders, and 7.3 cm for Grade-III shoulders. All Grade-III shoulders had >or=3 cm of shortening, and four of the five Grade-III shoulders showed limitation of elevation (abduction of <130 degrees ). None of the Grade-III shoulders had undergone arthrotomy within ten days after the onset of the disease. CONCLUSIONS: Inferior subluxation of the humeral head related to shoulder dysfunction resulting from early childhood septic arthritis accompanied humeral shortening of >or=3 cm and was only observed in patients who did not undergo arthrotomy of the shoulder within ten days after the onset of the infection.
BACKGROUND: Although humeral shortening as a sequel of septic arthritis of the shoulder in infants has been reported in previous studies, functional disorders of the shoulder resulting from humeral shortening have not yet been clarified. In this study, we retrospectively investigated the long-term outcome of septic arthritis of the shoulder in neonates and infants and examined the relationship between growth disturbance of the humerus and decreased range of motion with respect to glenohumeral joint laxity. METHODS: We reviewed the cases of fifteen patients (sixteen shoulders) with an age of a few days to 2.6 years at the onset of the disease who were followed from 5.0 to 17.9 years. We noted the initial treatment method and evaluated humeral length and shoulder function at the time of the final follow-up. For the final treatment results, we classified the shoulders with normal findings on radiographs as Grade I, those with humeral head deformity as Grade II, and those with humeral head deformity with inferior subluxation as Grade III. RESULTS: Primary treatment included arthrotomy in ten shoulders. The delay between the onset of the disease and surgery ranged from three to twenty-six days. At the time of the final follow-up, the results were Grade I in five shoulders, Grade II in six shoulders, and Grade III in five shoulders. The mean humeral shortening was 0.1 cm for Grade-I shoulders, 0.9 cm for Grade-II shoulders, and 7.3 cm for Grade-III shoulders. All Grade-III shoulders had >or=3 cm of shortening, and four of the five Grade-III shoulders showed limitation of elevation (abduction of <130 degrees ). None of the Grade-III shoulders had undergone arthrotomy within ten days after the onset of the disease. CONCLUSIONS: Inferior subluxation of the humeral head related to shoulder dysfunction resulting from early childhood septic arthritis accompanied humeral shortening of >or=3 cm and was only observed in patients who did not undergo arthrotomy of the shoulder within ten days after the onset of the infection.