Surgical repair of large segmental bone loss with the induced membrane technique: patient reported outcomes are comparable to nonunions without bone loss

OBJECTIVE

To compare the outcomes of patients with segmental bone loss who underwent repair with the induced membrane technique (IMT) with a matched cohort of nonunion fractures without bone loss.

DESIGN

Retrospective analysis on prospectively collected data.

SETTING

Academic medical center.

PATIENTS

Two cohorts of patients, those with upper and lower extremity diaphyseal large segmental bone loss and those with ununited fractures, were enrolled prospectively between 2013 and 2020. Sixteen patients who underwent repair of 17 extremities with segmental diaphyseal or meta-diaphyseal bone defects treated with the induced membrane technique were identified, and matched with 17 patients who were treated for 17 fracture nonunions treated without an induced membrane. Sixteen of the bone defects treated with the induced membrane technique were due to acute bone loss, and the other was a chronic aseptic nonunion.

MAIN OUTCOME MEASUREMENTS

Healing rate, time to union, functional outcome scores using the Short Musculoskeletal Functional Assessment (SMFA) and pain assessed by the Visual Analog Scale (VAS).

RESULTS

The initial average defect size for patients treated with the induced membrane technique was 8.85 cm. Mean follow-up times were similar with 17.06 ± 10.13 months for patients treated with the IMT, and 20.35 ± 16.68. months for patients treated without the technique. Complete union was achieved in 15/17 (88.2%) of segmental bone loss cases treated with the IMT and 17/17 (100%) of cases repaired without the technique at the latest follow up visit. The average time to union for patients treated with the induced membrane technique was 13.0 ± 8.4 months and 9.64 ± 4.7 months for the matched cohort. There were no significant differences in reported outcomes measured by the SMFA or VAS. Patients treated with the induced membrane technique required more revision surgeries than those not treated with an induced membrane.

CONCLUSION

Outcomes following treatment of acute bone loss from the diaphysis of long bones with the induced membrane technique produces clinical and radiographic outcomes similar to those of long bone fracture nonunions without bone loss that go on to heal.

LEVEL OF EVIDENCE

III.

Ten-step minimally invasive slalom unilateral laminotomy for bilateral decompression (sULBD) with navigation

BACKGROUND

Unilateral laminotomy for bilateral decompression (ULBD) is a MIS surgical technique that offers safe and effective decompression of lumbar spinal stenosis (LSS) with a long-term resolution of symptoms. Advantages over conventional open laminectomy include reduced expected blood loss, muscle damage, mechanical instability, and less postoperative pain. The slalom technique combined with navigation is used in multi-segmental LSS to improve the workflow and effectiveness of the procedure.

METHODS

We outline ten technical steps to achieve a slalom unilateral laminotomy for bilateral decompression (sULBD) with navigation. In a retrospective case series, we included patients with multi-segmental LSS operated in our institution using the sULBD between 2020 and 2022. The primary outcome was a reduction in pain measured by Visual Analogue Scale (VAS) for back pain and leg pain and Oswestry Disability Index (ODI).

RESULTS

In our case series (N = 7), all patients reported resolution of initial symptoms on an average follow-up of 20.71 ± 9 months. The average operative time and length of hospital stay were 196.14 min and 1.67 days, respectively. On average, VAS (back pain) was 4.71 pre-operatively and 1.50 on long-term follow-up of an average of 19.05 months. VAS (leg pain) decreased from 4.33 to 1.21. ODI was reported as 33% pre-operatively and 12% on long-term follow-up.

CONCLUSION

The sULBD with navigation is a safe and effective MIS surgical procedure and achieves the resolution of symptoms in patients presenting with multi-segmental LSS. Herein, we demonstrate the ten key steps required to perform the sULBD technique. Compared to the standard sULBD technique, the incorporation of navigation provides anatomic localization without exposure to radiation to staff for a higher safety profile along with a fast and efficient workflow.

Microbiome of infected fracture nonunion: Does it affect outcomes?

BACKGROUND

Infected fracture nonunions often require prolonged treatment and recovery courses. It is unclear whether the bacterial microbiome influences the time to healing as well as the eradication of infection. The goals of this study are (1) to assess the bacterial microbiome affecting infected nonunions and (2) to evaluate the effects of bacterial speciation on associated outcomes.

METHODS

Between 2006 and 2022, data from 551 adult patients from a single academic institution who presented with a fracture nonunion were analyzed retrospectively for infection. All patients underwent revision surgery with three sets of cultures obtained intra-operatively. Patients with significant intra-operative cultures were grouped into gram-positive and gram-negative culture cohorts. These patients were managed with a standardized protocol involving surgical debridement, nonunion site fixation, and culture-directed antibiotic treatment. Primary outcome was time to fracture union. Secondary outcomes included number of re-operations and eventual amputation or reconstructive surgery.

RESULTS

56 nonunion patients (10 %) were diagnosed with an infected nonunion (44 g-positive, 12 g-negative). Of these, 3 g-positive patients received an amputation or arthroplasty procedure prior to fracture union, and seven were lost to follow-up. There were no significant differences in age, gender, or nonunion site between cohorts. Most nonunions occurred in the lower extremity. The most common bacteria were staph species (54.3 %). 36 g-positive and 10 g-negative patients achieved fracture union. Time to union was on average 158.4 days longer in the gram-negative cohort-but did not reach statistical significance (446.8 days gram-positive, 662.3 days gram-negative, p = 0.69). There was no difference in re-operation rates (1.9 % gram-positive, 2.2 % gram-negative, p = 0.84).

CONCLUSIONS

Patients with infected nonunions had wide-ranging bacterial contamination that were treated successfully using a standardized protocol. However, patients with any gram-negative culture trended toward a delay in time to union.

No decay in outcomes at a mean 8 years following surgical treatment for aseptic fracture nonunion

PURPOSE

The purpose of this study is to compare medium to long term patient reported outcomes to one-year data for patients treated surgically for an aseptic fracture nonunion.

METHODS

305 patients surgically treated for a fracture-nonunion were prospectively followed. Data collected included pain scores measured by the Visual Analog Scale (VAS), clinical outcomes assessed by the Short Musculoskeletal Functional Assessment (SMFA), and range of motion. 75% of patients in this study had lower extremity fracture nonunions and 25% had upper extremity fracture nonunions. Femur fracture nonunions were the most common. Data at latest follow-up was compared to one-year follow-up using the independent t-test.

RESULTS

Sixty-two patients were available for follow-up data at an average of eight years. There were no differences in patient reported outcomes between one and eight years according to the standardized total SMFA (p = 0.982), functional index SMFA (p = 0.186), bothersome index SMFA (p = 0.396), activity index SMFA (p = 0.788), emotional index SMFA (p = 0.923), or mobility index SMFA (p = 0.649). There was also no difference in reported pain (p = 0.534). Range of motion data was collected for patients who followed up in clinic for an average of eight years after their surgical treatment. 58% of these patients reported a slight increase in range of motion at an average of eight years.

CONCLUSION

Patient functional outcomes, range of motion, and reported pain all normalize after one year following surgical treatment for fracture nonunion and do not change significantly at an average of eight years. Surgeons can feel confident in counseling patients that their results will last and they do not need to follow up beyond one year, barring pain or other complications.

LEVEL OF EVIDENCE

Level IV.

Patient obesity is associated with severity of proximal humerus fractures, not outcomes

PURPOSE

The purpose of this study is to evaluate the effect of obesity on the outcome of operatively treated proximal humerus fractures.

METHODS

Between December 2003 and October 2020, 240 patients with proximal humerus fractures requiring surgery were prospectively followed and classified according to the international AO/Orthopedic Trauma Association (AO/OTA) and Neer classifications. Patients' body mass indexes (BMI) were calculated and used to identify two groups, BMI ≥ 30 kg/cm (obese) and < 30 kg/cm (non-obese). Independent t tests were used for statistical analysis of continuous variables and χ² tests for categorical variables. Regression analysis was performed to determine if BMI was a predictor of fracture pattern severity as determined by the AO/OTA classification.

RESULTS

Overall, 223 patients who sustained proximal humerus fractures were analyzed. Patient age at time of injury was 60.5 ± 13.7 years. There were 67 AO/OTA 11A, 79 AO/OTA 11B, and 77 AO/OTA 11C fracture types. Seventy-two patients (32.3%) were obese. No significant differences were seen between groups in regard to demographic variables, Neer classification, or functional and clinical outcomes as determined by DASH scores and shoulder ROM, respectively. Statistical analyses confirmed that obesity is associated with more severe fracture patterns of the proximal humerus as categorized by the AO/OTA classification. An independent t test confirmed that BMI was significantly higher in the complex fracture group based on the AO/OTA classification (p = 0.047). Regression analysis also demonstrated that age (p = 0.005) and CCI (p = 0.021) were predictors of more severe fractures, while BMI approached significance (p = 0.055) based on the AO/OTA classification.

CONCLUSION

A significantly higher incidence of complex proximal humerus fracture patterns is observed in patients with higher body mass indexes based on the AO/OTA classification. Age and CCI are also associated with more severe fracture patterns of the proximal humerus as determined by the AO/OTA classification. No differences were seen in outcomes or complication rates between obese patients and non-obese patients.

LEVEL OF EVIDENCE

Level III.