Preventing Loss of Femoral Periprosthetic Bone Mineral Density in Cementless Total Hip Arthroplasty Using a Tapered Wedge Stem: A Retrospective, Cohort Study in Osteoporotic Patients Treated with Denosumab.

Purpose: Bone quality is an important issue in elderly osteoporotic patients who undergo total hip arthroplasty (THA) because periprosthetic fracture or aseptic loosening of implant caused by periprosthetic bone loss is a serious concern. Denosumab has been approved for osteoporosis patients. Thus, the purpose of this study was to investigate whether denosumab prevents loss of proximal femoral periprosthetic bone mineral density (BMD) in cementless THA using a tapered wedge stem in patients with osteoporosis. Methods: Seventy consecutive patients who had undergone primary THA were included in this study. Twenty-seven patients who received denosumab for osteoporosis formed the denosumab group, and 43 patients without denosumab formed the control group. Bone turnover markers and femoral periprosthetic BMD were measured at two weeks, six months, and 12 months after THA. BMD was evaluated in seven regions of interest according to the zones of Gruen. Results: BMD in zone 1 was significantly increased from baseline at both six and 12 months after THA in the denosumab group (10.0±10.2%, p<0.001 and 13.1±12.7%, p<0.001, respectively) and significantly decreased in the control group (-3.6±9.7%, p<0.05, and -5.9±9.4%, p<0.001, respectively). BMD in zone 7 was significantly decreased compared to baseline at both six and 12 months after THA in the control group (-19.2±20.2%, p<0.001 and -22.3±16.8%, p<0.001, respectively) but not in the denosumab group (-0.7±18.5% and -1.1±16.6%, respectively). The use of denosumab for THA patients with osteoporosis was independently related to preventing loss of periprosthetic BMD of the femur at 12 months after surgery in zones 1 (p<0.001) and 7 (p<0.001) on multivariate analysis. Conclusions: Denosumab significantly increased proximal femoral periprosthetic BMD in zone 1 and prevented loss of BMD in zone 7 in patients with osteoporosis after cementless THA using a tapered wedge stem at both seven and 12 months. Future studies of denosumab treatment following THA in patients with osteoporosis should focus on clinical outcomes such as the risk of periprosthetic fracture and revision THA.

Degenerative Lumbar Spondylolisthesis Patients With Movement-related Low Back Pain Have Less Postoperative Satisfaction After Decompression Alone.

STUDY DESIGN: Retrospective analysis of prospectively collected multicenter observational data. OBJECTIVE: The aim was to examine the preoperative factors affecting postoperative satisfaction following posterior lumbar interbody fusion (PLIF) and microendoscopic muscle-preserving interlaminar decompression (ME-MILD) in patients with degenerative lumbar spondylolisthesis (DLS). SUMMARY OF BACKGROUND DATA: The technique involved in DLS surgery may either be decompression alone or decompression-fixation. Poor performance may occur after either of these surgical treatments. The author hypothesized that evaluating the correlation between preoperative quality of life and postoperative performance would aid in determining the optimal procedure. MATERIALS AND METHODS: This study included 138 patients who underwent surgery for 1-level mild DLS. The authors performed PLIF for 79 patients and ME-MILD for 59 patients. When the satisfaction subscale of the Zurich Claudication Questionnaire exceeded 2 points, postoperative satisfaction was considered poor. The clinical characteristics were investigated. Responses to preoperative health-related quality of life questionnaires, such as the Japanese Orthopedic Association Back Pain Evaluation Questionnaire (JOABPEQ), short form-36 health survey (SF-36), and visual analog scale, were compared between the satisfied and unsatisfied groups. RESULTS: In the PLIF group, no endogenous factors influenced postoperative satisfaction. The ME-MILD cohort's satisfied and unsatisfied patients differed significantly in terms of preoperative lumbar spine dysfunction ( P <0.001) items of the JOABPEQ, role physical ( P =0.03), and role emotional ( P =0.03) items of the SF-36. A strong correlation ( r =-0.609 P =0.015) was found between preoperative lumbar spine dysfunction and postoperative satisfaction. CONCLUSIONS: In the ME-MILD group, preoperative lumbar spine function was correlated with postoperative satisfaction. Decompression alone may be ineffective in cases with decreased lumbar spine function prior to surgery. The degree of low back pain on movement should be considered before selecting the surgical method. LEVEL OF EVIDENCE: 3.

Histological demonstration of the gas precursor in a symptomatic L5-S1 disc herniation containing gas: A case report.

Vacuum phenomenon is a commonly observed radiological entity in the degenerated intervertebral discs of the lumbar spine in the elderly population. The entity is frequently asymptomatic. Although disc herniation containing gas (DH-CoG) is commonly associated with the vacuum phenomenon, DH-CoG associated with clinical symptoms is a rare condition. There are very few reports which have histologically demonstrated the existence of the gas itself within DH-CoG. Herein, we report a rare case of a 65-year-old female with symptomatic DH-CoG at L5/S1. The patient was admitted to our hospital with a one-month history of pain in the left buttock and leg in addition to neurogenic claudication. Roentgenograms illustrated a degenerative lumbar spine with the vacuum phenomenon at the L5/S1 disc space. Computed tomography showed a round and low-density lesion within the spinal canal at left L5/S1. Additionally, a lesion characterized by an iso- and partially hypointense signal on T1 and hypointense signal on T2 was detected in magnetic resonance imaging (MRI) by the spin-echo method. The decision for posterior lumbar interbody fusion surgery using pedicle screws was made as the symptoms had not responded to the conservative treatment. After a degenerated prolapsed nucleus was carefully extracted, the specimen was sent to the laboratory for histopathological analysis. The prolapsed nucleus of DH-CoG histologically showed many small vacuoles containing degenerated mucopolysaccharides. The left leg pain drastically resolved on the first post-operative day, and no recurrence had been observed. Degenerated mucopolysaccharide may be a precursor of nitrogen or "the gas itself" in DH-CoG. Surgical intervention for DH-CoG should be considered if conservative treatment fails.

Comparison of Posterior Lumbar Interbody Fusion and Microendoscopic Muscle-preserving Interlaminar Decompression for Degenerative Lumbar Spondylolisthesis With >5-Year Follow-up.

STUDY DESIGN: Retrospective analysis of prospectively collected observational multicenter data. OBJECTIVE: To compare the clinical results and rates of revision surgery after posterior lumbar interbody fusion (PLIF) and microendoscopic muscle-preserving interlaminar decompression (ME-MILD) in patients with single-level, mild degenerative lumbar spondylolisthesis (DLS) and follow-up of at least 5 years. SUMMARY OF BACKGROUND DATA: Surgery for symptomatic DLS remains controversial. Evaluating long-term results may reveal problems such as adjacent segmental diseases of the PLIF and decreased quality of life because of slippage and restenosis of the ME-MILD. METHODS: We enrolled 116 patients who underwent PLIF (79 patients) or ME-MILD (37 patients). Operative times, blood losses, surgical complications, Short-Form 36 (SF-36), Japanese Orthopedic Association (JOA) score, the JOA Back Pain Questionnaire (JOABPEQ), visual analog scales (VAS), and Zurich Claudication Questionnaire (ZCQ) were evaluated. RESULTS: PLIF was observed to require significantly longer operative times and entailed greater operative blood losses than did ME-MILD (151.1 vs. 119.9 min; 202.2 vs. 6.4 mL, respectively). Surgery-related complications were identified in 3 cases in the PLIF group and 2 cases in the ME-MILD group. Seventy-eight patients (50 and 28 patients in the PLIF and ME-MILD groups, respectively) were successfully followed-up for >5 years. The follow-up rate was 67.2%. No significant differences between the groups were found in terms of preoperative and postoperative JOA scores, postoperative JOABPEQ, VAS, or ZCQ. Significant improvements in JOA scores were observed in both groups. Significant improvements in the SF-36 were observed in all subscales except in role physical, general health, vitality, and mental health in the ME-MILD group. Revision surgical procedures were performed in 2 patients in the ME-MILD group and 4 patients in the PLIF group. CONCLUSIONS: PLIF and ME-MILD resulted in equivalent improvements in SF-36 and JOA scores. There were no differences in revision surgery rates among patients with single-level, mild DLS. LEVEL OF EVIDENCE: Level III-a retrospective analysis.

Limaprost or Pregabalin: Preoperative and Postoperative Medication for Pain due to Lumbar Spinal Stenosis.

PURPOSE: We aimed to evaluate the incidence of (and risk factors for) postoperative pregabalin and/or limaprost to treat persistent numbness and/or pain of the lower extremities after lumbar spinal stenosis (LSS) surgery. METHODS: Medical records of 329 patients (168 men, 161 women; average age 70 years) were retrospectively reviewed for data on the duration of LSS diagnosis; LSS disease; preoperative medication (limaprost, pregabalin, or combined limaprost/pregabalin; duration); symptoms; preoperative/postoperative intermittent claudication (IC); operation type; and postoperative medication and period. RESULTS: Limaprost, pregabalin, and combined limaprost/pregabalin were prescribed preoperatively for 43%, 7%, and 5% of patients, respectively. At an average of 21 months postoperatively, limaprost, pregabalin, and combined therapy were prescribed in 11%, 8%, 4% of patients, respectively. Medication requirement was significantly lower postoperatively than preoperatively (P < 0.0001). Significant risk factors for required postoperative medication were required preoperative medication (odds ratio [OR] 3.088, 95% confidence interval [CI] 1.679 to 5.681]; postoperative period (OR 1.063, 95% CI 1.031 to 1.096); and postoperative IC (OR 3.868, 95% CI 1.481 to 10.103). A negative impact from postoperative medication was seen in patients who had undergone decompression surgery (OR 0.589, 95% CI 0.377 to 0.918). CONCLUSIONS: Overall, 23% of LSS patients required medication for pain and/or numbness at 21 months postoperatively. Significant factors portending required postoperative medication were preoperative medication, longer postoperative period, and postoperative IC. A negative influence from postoperative medication was seen in patients who had undergone decompression surgery without fusion.

Osteolysis of the Greater Trochanter Caused by a Foreign Body Granuloma Associated with the Ethibond® Suture after Total Hip Arthroplasty.

The present case shows a case of progression of osteolysis of the greater trochanter caused by a foreign body granuloma associated with the number 5 Ethibond suture in cementless THA with the direct lateral approach that was completely healed by removal of the Ethibond suture. A 55-year-old Japanese woman with secondary osteoarthritis caused by acetabular dysplasia underwent left cementless THA with the direct lateral approach. After setting of the total hip prosthesis, the gluteus medius muscle and vastus lateralis muscle were reattached to the greater trochanter through two bone tunnels using number 5 Ethibond EXCEL sutures. The left hip pain disappeared after surgery, but the bone tunnels enlarged gradually and developed osteolysis at 10 weeks. The removal of the Ethibond sutures and debridement improved the osteolysis. Histological examination showed the granuloma reaction to a foreign body with giant cell formation. The Ethibond suture has the lowest inflammatory tissue reaction and relatively high tension strength among nonabsorbable suture materials. However, number 5 Ethibond has the potential to cause osteolysis due to a foreign body granuloma, as in the present case.

ACDF with a PEEK cage clinically provides a good outcome with minor donor site morbidity despite unsatisfactory radiological findings-A prospective cohort study of a PEEK cage in stand-alone usage.

STUDY DESIGN: A prospective cohort study was conducted on patients with anterior cervical decompression and fusion (ACDF) with a polyetheretherketone cage (PEEKc). BACKGROUND: Advantages of a PEEKc have been proposed in the study. However, benefits of using a PEEKc in ACDF are still controversial. OBJECTIVE: To investigate the advantages of a PEEKc in ACDF. MATERIALS AND METHODS: A total of 27 patients was enrolled in the study. The mean age of patients was 55±10 years (mean±standard deviation). The mean duration of symptoms was 17±21 months. Surgery was conducted at C3/4 in 1, C4/5 in 3, C5/6 in 11, C6/7 in 9, C7/T1 in 2, and C5/6/7 in 1 patient. The mean follow-up period was 2.1±1.3 years. Clinical outcomes were analyzed by the Japanese Orthopedic Association Scores (JOA scores) and its recovery rate. Perioperative complications were also investigated. Radiologically, studies were conducted on interbody lordotic angle (IBLA), interbody height (IBH), and bone fusion rates. RESULTS: The JOA score was 14.7±1.4 preoperatively and 16.3±1.3 at the final follow-up. A significant improvement was observed (p<0.05). The mean recovery rate of JOA scores was 74.0±25.0%. The preoperative IBLA was 0.5±6.1°. The mean IBLA at the final follow-up was 1.9±5.6°. The preoperative IBH was 34.2±3.5 mm. The mean IBH at the final follow-up was 34.3±3.5 mm. No significant improvement in IBLA and IBH was observed. A complete union rate at 1 year and 2.3 years (range, 2.0-6.0) after surgery was 29% (8/28 segments) and 61% (11/18 segments). No major complications were observed. CONCLUSIONS: Despite an unsatisfactory bone union rate and no significant improvement in IBLA and IBH at the final follow-up, ACDF with a PEEKc clinically provided a stable outcome with less surgical invasion and minor donor-site morbidity.

PLIF with a titanium cage and excised facet joint bone for degenerative spondylolisthesis--in augmentation with a pedicle screw.

OBJECTIVES: To determine the validity of posterior lumbar interbody fusion (PLIF) using a titanium cage filled with excised facet joint bone and a pedicle screw for degenerative spondylolisthesis. METHODS: PLIF using a titanium cage filled with excised facet joint bone and a pedicle screw was performed in 28 consecutive patients (men 10, women 18). The mean age of the patients was 60 years (range, 52 to 75 y) at the time of surgery. The mean follow-up period was 2.3 years (range, 2.0 to 4.5 y). The operation was done at L3/4 in 5, L4/5 in 20, and L3/4/5 in 3 patients. The mean operative bleeding was 318+/-151 g (mean+/-standard deviation), and the mean operative time was 3.34+/-0.57 hours per fixed segment. Clinical outcome was assessed by Denis' Pain and Work scale. Radiologic assessment was done using Boxell's method. Fusion outcome was assessed using an established criteria. RESULTS: On Pain scale, 20 and 8 patients were rated P4 and P5 before surgery, and 11, 12, 2, 2, and 1 patients were rated P1, P2, P3, P4, and P5 at final follow-up, respectively. On Work scale (for only physical labors), 12 and 9 patients were rated W4 and W5, before surgery, and 12, 5, 1, and 3 patients were rated W1, W2, W3 and W5 at final follow-up, respectively. There was significant difference in clinical outcome (P<0.01, Wilcoxon singled-rank test) The mean %Slip and Slip Angle was 17.9+/-8.1% and 3.9+/-5.8 degrees before surgery. The mean % Slip and Slip Angle was 5.4+/-4.4% and -2.0+/-4.8 degrees at final follow-up. There was a significant difference between the values (P<0.01, paired t test). "Union" and "probable union" was determined in 29 (93.5%) and 2 (6.5%) of 31 operated segments at 2.3 years (range, 2.0 to 4.5 y), postoperatively. CONCLUSIONS: PLIF using a titanium cage filled with excised facet joint bone and a pedicle screw provided a satisfactory clinical outcome and an excellent union rate without harvesting and grafting the autologous iliac bone.