In this retrospective study postoperative subscapularis (SSC) function was measured with an electronic force measurement plate (FMP) and clinical scores and correlated with SSC-muscle cross sectional area on defined MRI-sequences.

82 patients with subscapularis tears (34 isolated SSC tears and 48 combined SSC/SSP tears) were followed up at a mean of 38 (24–72) months after tendon reconstruction with the Constant score (CS) and clinical SSC-tests (Napoleon test, Lift off test). SSC-muscle function was assessed in the belly-press- and the lift off position using a custom made electronic FMP (force in Newton). SSC muscle strength values were compared with the contra-lateral side. SSC-muscle atrophy (muscle cross sectional area in mm²) was measured on standardised sagittal MRI-planes and compared with a healthy matched control group (CG) (Mann-Whitney-U-Test).

The mean CS improved from 51p to 81p in isolated tears (group 1) and from an average 47 p to 78 p in combined tears (group 2) (each p< 0.01). Overall 85% of the patients rated their result as good or excellent. Positive and intermediate postop. Napoleon tests were still present in 30% in group 1 and in 25% in group 2. Mean postoperative SSC-muscle strength in the belly-press position averaged 64 N (contralatera sidel-CL: 86 N) in group 1 and 81 N (CL: 91 N) in group 2. Lift-off test strength averaged 36 N (CL: 69 N) in group 1 and 50 N (CL: 63 N) in group 2 (each p< 0.05). Postoperative MRI revealed a significant reduced SSC muscle cross sectional area for the operated side compared with the CG (group 1: SSC: 1974 mm²; CG 2980 mm² p< 0,05; group 2: SSC: 1829 mm²; CG 2406 mm² − SSP: 570 mm²; CG 812 mm² each p< 0,05).

Despite good clinical results after reconstruction of isolated and combined subscapularis tears a marked subscapularis strength deficit remains that is not reflected in the Constant Score, but can be detected with the new measurement device. Additionally a subscapularis muscle atrophy remains in the postoperative course that cannot be reversed by surgery.

We treated 58 patients with osteoid osteoma by CT-guided radiofrequency ablation (RF). In 16 it followed one or two unsuccessful open procedures. It was performed under general anaesthesia in 48, and spinal anaesthesia in ten. The nidus was first located by thin-cut CT (2 to 3 mm) sections. In hard bony areas a 2 mm coaxial drill system was applied. In softer areas an 11-gauge Jamshidi needle was inserted to allow the passage of a 1 mm RF probe into the centre of the nidus. RF ablation was administered at 90°C for a period of four to five minutes.

Three patients had recurrence of pain three, five and seven months after treatment, respectively, and a second percutaneous procedure was successful. Thus, the primary rate of success for all patients was 95% and the secondary rate was 100%. One minor complication was encountered.

CT-guided RF ablation is a safe, simple and effective method of treatment for osteoid osteoma.