The Influence of Multilevel Spinal Deformity Surgery on the EuroQol 5 Dimensions' (EQ-5D) Questionnaire and Residential Status in the Elderly: A Prospective, Observational, Multicenter Study

STUDY DESIGN

Multicenter, international prospective study.

OBJECTIVE

This study investigated the clinical outcome up to 2 years after multi-level spinal deformity surgery in the elderly by reporting the minimal clinically important difference (MCID) of EuroQol 5-dimensions (EQ-5D), EQ-VAS, and residential status.

METHODS

As an ancillary study of 219 patients ≥60 years with spinal deformity undergoing primary instrumented fusion surgery of ≥5 levels, this study focuses on EQ-5D (3-L) as the primary outcome and EQ-VAS and residential status as secondary outcomes. Data on EQ-5D were compared between pre-operatively and postoperatively at 10 weeks, 12 months, and 24 months. An anchor-based approach was used to calculate the MCID.

RESULTS

The EQ-5D index and EQ-VAS, respectively, improved significantly at each time point compared to pre-operatively (from .53 (SD .21) and 55.6 (SD 23.0) pre-operatively to .64 (SD .18) and 65.8 (SD 18.7) at 10 weeks, .74 (SD .18) and 72.7 (SD 18.1) at 12 months, and .73 (SD .20) and 70.4 (SD 20.4) at 24 months). 217 (99.1%) patients lived at home pre-operatively, while 186 (88.6%), 184 (98.4%), and 172 (100%) did so at 10 weeks, 12 months, and 24 months, respectively. Our calculated MCID for the EQ-5D index at 1 year was .22 (95% CI .15-.29).

CONCLUSIONS

The EQ-5D index significantly increased at each time point over 24 months after ≥5 level spinal deformity surgery in elderly patients. The MCID of the EQ-5D-3 L was .22. Patients living at home pre-operatively can expect to be able to live at home 2 years postoperatively.

Shoulder Muscle Strength and Neuromuscular Activation 2 Years after Reverse Shoulder Prosthesis-An Experimental Case Control Study

Although reverse shoulder arthroplasty (RSA) has shown successful postoperative outcomes, little is known about compensatory activation patterns of remaining shoulder muscles following RSA. The purpose of this experimental case control series was to investigate shoulder muscle strength and neuromuscular activation of deltoid and teres minor muscles 2 years after RSA. Humerus lengthening, center-of-rotation medialization, maximal voluntary strength, and electromyographic (EMG) activity were compared between the operated and the non-operated side of 13 patients (mean age: 73 years). Shoulder muscle strength was significantly lower on the operated side for external rotation (−54%), internal rotation (−20%), and adduction (−13%). Agonist deltoid EMG activity was lower on the operated side for shoulder flexion, extension, and internal and external rotation (p < 0.05). Antagonist deltoid coactivation was higher on the operated side for external rotation (p < 0.001). Large correlation coefficients were observed between shoulder adductor strength asymmetry and both center-of-rotation medialization (r = −0.73) and humerus lengthening (r = 0.71). Shoulder abduction strength and neuromuscular activation were well preserved 2 years after RSA, while persistent strength and activation deficits were observed for shoulder adduction and internal and external rotation. Additional studies are required to elucidate shoulder neuromuscular activation patterns before and after RSA to support decision making for surgical, implant design, and rehabilitation choices.

Accuracy of CT-navigated pedicle screw positioning in the cervical and upper thoracic region with and without prior anterior surgery and ventral plating

AIMS

We aimed to retrospectively assess the accuracy and safety of CT navigated pedicle screws and to compare accuracy in the cervical and thoracic spine (C2-T8) with (COMB) and without (POST) prior anterior surgery (anterior cervical discectomy or corpectomy and fusion with ventral plating: ACDF/ACCF).

PATIENTS AND METHODS

A total of 592 pedicle screws, which were used in 107 consecutively operated patients (210 COMB, 382 POST), were analysed. The accuracy of positioning was determined according to the classification of Gertzbein and Robbins on post-operative CT scans.

RESULTS

High accuracy was achieved in 524 screws (88.5%), 192 (87.7%) in the cervical spine and 332 (89%) in the thoracic spine, respectively. The results in the two surgical groups were compared and a logistic regression mixed model was performed to analyse the risk of low accuracy. Significantly lower accuracy was found in the COMB group with 82.9% versus 91.6% in the POST group (p = 0.036). There were no neurological complications, but two vertebral artery lesions were recorded. Three patients underwent revision surgery for malpositioning of a screw. Although the risk of malpositioning of a screw after primary anterior surgery was estimated to be 2.4-times higher than with posterior surgery alone, the overall rates of complication and revision were low.

CONCLUSION

We therefore conclude that CT navigated pedicle screws can be positioned safely although greater caution must be taken in patients who have previously undergone anterior surgery. Cite this article: Bone Joint J 2017;99-B:1373-80.

Osteoporosis Is the Most Important Risk Factor for Odontoid Fractures in the Elderly

Traumatic odontoid fractures (TOFs) have been described as the most common injury affecting the C-spine in the elderly. Previous studies have identified degenerative changes and bone loss as important predisposing factors. However, their interaction and respective age-adjusted impact needs further clarification. We conducted a retrospective analysis of 5303 patients (aged ≥60 years) admitted to a level I trauma center between January 2008 and January 2016 who underwent CT imaging of the C-spine. Ninety-two patients with TOF and 80 patients with other cervical spine fractures (OCSF) were identified and a respective 3:1 age- and sex-matched control group without fractures after trauma was built. In all groups, cervical bone mineral density (cBMD) was determined using phantom calibration, and degenerative changes were evaluated in a qualitative manner. In all groups, the severity of degenerative changes of the C-spine increased with age (all p < 0.05) and was inversely correlated with cBMD (all p < 0.05). cBMD was the only significant predictor of a TOF in a multivariate logistic regression model (adjusted odds ratio [OR] = 3.066, 95% confidence interval [CI] 1.432-6.563 for cervical osteoporosis). An association between odontoid cysts and TOF reached significance only in Anderson and D'Alonzo (A&D) type II TOFs (aOR = 1.383; 95% CI 1.012-1.890). Patients with OCSFs, compared with patients with TOFs, were younger (median 74 versus 83 years) and had a higher cBMD (median 208 mg/mL versus 172 mg/mL). No differences were observable when comparing cBMD and grades of degenerative changes between OCSFs and their control group (all p >0.1). Decreased cBMD is the major predisposing factor for the occurrence of TOF but not for OCSF in the elderly. The severity of odontoid cysts was found to be a cBMD-independent factor associated with A&D type II TOFs. However, degenerative changes in the odontoid neighboring joints seem to be an epiphenomenon of bone loss and older age but do not independently predispose for TOF. © 2017 American Society for Bone and Mineral Research.

Propionibacterium prosthetic joint infection: experience from a retrospective database analysis

BACKGROUND

With improved diagnostic methods and longer prosthesis indwelling time, the frequency of diagnosed Propionibacterium prosthetic joint infections (PJI) is increasing. Data on clinical, microbiological, radiological and surgical treatment are limited, and importance of this organism in PJI is probably underestimated.

MATERIALS AND METHODS

We retrospectively analyzed patients with PJI caused by Propionibacterium spp. diagnosed at our institution between 2000 and 2012. Patient data were retrieved through chart review, and the outcome was evaluated at patient follow-up visits.

RESULTS

Of 15 included patients (median age 65 years, range 44-87), 8 hip, 4 shoulder, 2 knee and 1 ankle PJI were recorded. The median time from implantation to diagnosis of PJI was 44.2 months (range 2-180 months). Most PJI (8 patients, 53 %) were diagnosed late (>24 months after arthroplasty). Persistent pain was present in 13, local joint symptoms in 8, fever in 4 and sinus tract in 3 patients. Radiological signs of loosening were present in 11 patients (73 %). Organisms were detected in intraoperative biopsy (n = 5), sonication (n = 4) or preoperative joint puncture (n = 4). In three cases coinfection with a coagulase-negative staphylococcus was diagnosed. Revision surgery was performed in all cases. After a mean follow-up of 16 months after revision surgery (range 4-37 months), 14 patients (93 %) showed no signs or symptoms of infection and had a functional prosthesis; one patient experienced a new infection with another organism (Staphylococcus epidermidis).

CONCLUSION

Patients with persistent postoperative pain and/or loosening of implants should be screened for PJI with low-virulent organisms such as Propionibacterium, including.