The learning curve for robotic-assisted total hip arthroplasty in low, medium, and high-volume surgeons

Background

Robotic systems have been designed to increase the accuracy of implant alignment in total knee and hip arthroplasty. This technology is associated with a learning curve for the operative time to reach peak efficiency in its use. Prior studies done on high-volume orthopedic surgeons have suggested a learning curve of 14-35 cases for robotic-assisted total hip arthroplasty (THA). It is unclear if this learning curve is different for surgeons with lower volumes.

Methods

Data was collected retrospectively from 299 THA procedures done by three different surgeons, with low (1-15 cases/year), medium (16-50), and high (51+) volume caseload. The learning curve was assessed primarily by average operative time from cases 1-20, 21-50, and 51+.

Results

The high-volume surgeon had a learning curve of 20 cases, while the low and medium volume surgeons had no significant decrease in their operative time through the cases included in the study (20 and 63, respectively).

Conclusions

High volume surgeons have a learning curve of about 20 cases, while low and medium volume surgeons have a longer curve, which was not able to be measured in this study.

Appropriate Use Criteria for Hyaluronic Acid in the Treatment of Knee Osteoarthritis in the United States

OBJECTIVE

A workgroup of clinical experts has developed an Appropriate Use Criteria (AUC) for the use of hyaluronic acid (HA) in the treatment of osteoarthritis (OA) of the knee. The increasingly broad and varied use of HA injections, lack of published clinical guidance, and limited coverage for their use has created the imperative to establish appropriateness criteria.

METHODS

The experts of this workgroup represent rheumatology, orthopedic surgery, physiatry, sports medicine, and nursing clinicians with substantive knowledge of intra-articular HA therapy. This workgroup utilized the results of a systematic review of evidence, expert clinical opinion, and current evidence-based clinical practice guidelines to develop appropriateness criteria for the use of intra-articular HA for knee OA in 17 real-world clinical scenarios.

RESULTS

The workgroup scored the appropriateness of treatment of each patient scenario using a 9-point scale to designate a treatment as appropriate (7-9), uncertain (4-6), or inappropriate (1-3). Six scenarios were scored as appropriate, 10 scenarios were scored as uncertain, and 1 scenario was scored as inappropriate.

CONCLUSION

This article can assist clinicians in shared decision-making by providing best practices in considering HA injections for knee OA treatment. Moreover, this AUC article can aid payers and policy makers in determining reimbursement and preauthorization policies and more appropriately managing health care resources. It is clear that further research is still necessary-particularly in patient populations differentiated by OA severity-that may benefit the greatest from the use of HA injections for the treatment of knee OA.

Polyaxial Screws in Locked Plating of Tibial Pilon Fractures

This study examined the axial and torsional stiffness of polyaxial locked plating techniques compared with fixed-angle locked plating techniques in a distal tibia pilon fracture model. The effect of using a polyaxial screw to cross the fracture site was examined to determine its ability to control relative fracture site motion. A laboratory experiment was performed to investigate the biomechanical stiffness of distal tibia fracture models repaired with 3.5-mm anterior polyaxial distal tibial plates and locking screws. Sawbones Fourth Generation Composite Tibia models (Pacific Research Laboratories, Inc, Vashon, Washington) were used to model an Orthopaedic Trauma Association 43-A1.3 distal tibia pilon fracture. The polyaxial plates were inserted with 2 central locking screws at a position perpendicular to the cortical surface of the tibia and tested for load as a function of axial displacement and torque as a function of angular displacement. The 2 screws were withdrawn and inserted at an angle 15° from perpendicular, allowing them to span the fracture and insert into the opposing fracture surface. Each tibia was tested again for axial and torsional stiffness. In medial and posterior loading, no statistically significant difference was found between tibiae plated with the polyaxial plate and the central screws placed in the neutral position compared with the central screws placed at a 15° position. In torsional loading, a statistically significant difference was noted, showing greater stiffness in tibiae plated with the polyaxial plate and the central screws placed at a 15° position compared with tibiae plated with the central screws placed at a 0° (or perpendicular) position. This study showed that variable angle constructs show similar stiffness properties between perpendicular and 15° angle insertions in axial loading. The 15° angle construct shows greater stiffness in torsional loading.

Platelet-Rich Plasma in Addition to Rehabilitation for Acute Hamstring Injuries in NFL Players: Clinical Effects and Time to Return to Play

BACKGROUND

Platelet-rich plasma (PRP) injections have been proposed to hasten soft tissue healing. There is a lack of evidence in the current literature to support their efficacy in elite athletes.

PURPOSE

To investigate the effects of the addition of PRP to rehabilitation in the treatment of acute hamstring injuries in professional National Football League (NFL) players and to report the time to return to play.

STUDY DESIGN

Case control study.

METHODS

Ten NFL players with similar hamstring injury patterns were retrospectively divided into 2 groups. The treatment group (PRP; n = 5) was injected with PRP and the control group (non-PRP; n = 5) was not injected; both groups completed a rehabilitation program. The PRP injections were administered under ultrasound guidance with precise localization of the injury site, within 24 to 48 hours of injury. Age, muscle involved, extent of injury, grading, and time to return to play were noted. Descriptive statistics and the exact Wilcoxon rank-sum test were used for data analysis.

RESULTS

The mean age was 23 years (range, 22-27 years) for the PRP group and 26 years (range, 22-28 years) for the non-PRP group (P = .42). The median longitudinal extent of the injury was 14 cm (range, 9-18 cm) in the PRP group and 15 cm (range, 9-16 cm) in the non-PRP group (P = .77). The average transverse extent of the injury in the PRP and non-PRP groups was 4 cm (range, 1.6-6 cm) and 3.5 cm (range, 2-5 cm), respectively, and the respective average anteroposterior extent was 4 cm (range, 1.9-5 cm) and 2.9 cm (range, 1.5-4 cm). The long head of biceps femoris was most commonly involved (4 in each group), with a single tear of the semimembranosus in each group. The median injury classification was grade 2 in both groups. The median time to return to play was 20 days (range,16-30 days) in the PRP group and 17 days (range, 8-81 days) in the non-PRP group (P = .73).

CONCLUSION

There were no significant differences in recovery from hamstring injury between treatment with PRP and routine rehabilitation. A larger, randomized controlled trial is warranted.

Procedure simplification: the role of single-use instruments in total knee arthroplasty

In orthopaedic surgery, surgical site contamination leading to periprosthetic infections is a major concern with important morbidity, financial and emotional burden. Single-use instruments developed for total knee arthroplasties are intended to simplify the surgical procedure, decrease the number of surgical trays that require sterilization and reprocessing, decrease the incidence of possible contamination through breaks in surgical wraps, and improve operating room efficiency. As the demand for total knee arthroplasty continues to rise, a greater burden on the healthcare system may be created. The use of single-use instruments, cutting guides, and trials will play an increasing role in total knee arthroplasty through improved operating room efficiency.

Nonunion of fibula: a systematic review

PURPOSE

The purpose of this systematic review was to analyse the available evidence regarding nonunions of the fibula. We focussed on the incidence, risk factors, evaluation, and treatment modalities for fibular nonunions as evident in the current literature and propose a treatment algorithm.

METHODS

This was an Institutional Review Board (IRB) exempt study performed at a level one trauma centre. We systematically reviewed the published evidence on fibular nonunion or delayed union from 1950 to February, 2011.

RESULTS

Twelve articles were included in this systematic review. In summary, nonunion of the fibula is becoming increasingly more common in association with intramedullary nailing of concomitant tibial shaft fractures. A treatment algorithm for nonunion of the fibula has been proposed.

CONCLUSIONS

The suspicion for nonunion of the fibula should be heightened in lower leg fractures if the patient is symptomatic, and the progression of healing is not as expected. Ideally, prospective, multicentre studies would be performed to provide more rigorous data on the incidence, risk factors, and optimum treatment.

Nonunion of fibula: a systematic review

PURPOSE

The purpose of this systematic review was to analyse the available evidence regarding nonunions of the fibula. We focussed on the incidence, risk factors, evaluation, and treatment modalities for fibular nonunions as evident in the current literature and propose a treatment algorithm.

METHODS

This was an Institutional Review Board (IRB) exempt study performed at a level one trauma centre. We systematically reviewed the published evidence on fibular nonunion or delayed union from 1950 to February, 2011.

RESULTS

Twelve articles were included in this systematic review. In summary, nonunion of the fibula is becoming increasingly more common in association with intramedullary nailing of concomitant tibial shaft fractures. A treatment algorithm for nonunion of the fibula has been proposed.

CONCLUSIONS

The suspicion for nonunion of the fibula should be heightened in lower leg fractures if the patient is symptomatic, and the progression of healing is not as expected. Ideally, prospective, multicentre studies would be performed to provide more rigorous data on the incidence, risk factors, and optimum treatment.

Anterolateral and medial locking plate stiffness in distal tibial fracture model

BACKGROUND

The purpose of this study was to compare the axial and torsional stiffness between anterolateral and medial distal tibial locking plates in a pilon fracture model.

MATERIALS AND METHODS

The biomechanical stiffness of anterolateral or medial plated pilon fracture models was evaluated. Six Sawbones Composite Tibiae with a simulated pilon fracture representing varus or valgus comminution (OTA 43-A2.2) were plated with a Synthes 3.5-mm contoured LCP anterolateral or medial locking distal tibia plate. Load as a function of axial displacement and torque as a function of angular displacement were recorded. Each tibia was tested with a fracture wedge in place and removed with a medial and then anterolateral plate.

RESULTS

Loading the tibial plateau medial to the central axis, no significant difference in mean stiffness between the anterolateral and medial plates was demonstrated with the fracture wedge in place. A significant difference was demonstrated with the wedge removed. Loading the plateau posterior to the central axis, no significant difference in mean stiffness between plates was demonstrated with the wedge in place or removed. With the wedge in place, there was a significant difference in mean torsional stiffness for clockwise rotation, but not counterclockwise rotation. With the wedge removed, no significant difference appeared in mean stiffness for clockwise and counterclockwise rotation.

CONCLUSION

Distal tibia extra-articular fractures stabilized with anterolateral or medial locking plate constructs demonstrated no statistically significant difference in biomechanical stiffness in compression and torsion testing.

CLINICAL RELEVANCE

We believe this study indicates the primary concern when treating a pilon fracture may be soft-tissue considerations. Further clinical studies are required before definitive changes can be recommended regarding pilon fracture fixation.

Venous thromboembolism in shoulder surgery: a systematic review

Although it is generally believed that venous thromboembolism (VTE) after shoulder surgery is very rare, there are increasing reports of deep venous thrombosis (DVT) and pulmonary embolism (PE) associated with shoulder surgery. To our knowledge only few studies have reviewed the available evidence on the subject. The purpose of this study was to review the available evidence in the published literature regarding incidence, risk factors, diagnosis and management of DVT/PE following shoulder surgery (Level IV evidence).

The effect of salinity on morphological characteristics of seven rice (Oryza sativa) genotypes differing in salt tolerance

The effect of salinity on morphological characters of salt tolerant genotypes PVSB9, PVSB19, PNR381, PNR519, Iratom24 and salt sensitive genotype NS15 along with one standard check salt tolerant rice cultivar Pokkali were assessed in two factors Completely Randomized Design with four replications. Seven rice genotypes in combination with six levels of salinity (0, 3, 6, 9, 12 and 15 dS m(-1)) were randomly assigned in 168 experimental plastic pots. The different morphological characters studied include plant height, total number of tillers, Root Dry Weight (RDW), Shoot Dry Weight (SDW) and Total Dry Matter (TDM) content of the selected rice genotypes in view to evaluate their response at different salinity levels. The results on the effect of morphological characters indicated that plant height, total tillers, root, shoot and total dry matter were significantly decreased by the application of salinity. The genotypes Pokkali, PVSB9, PVSB19 showed significantly higher values and the lowest value of all these characters were recorded in NS15. A sharp decrease in percent relative-plant height, RDW, SDW, TDM, total tillers were found in susceptible genotype NS 15 after 3 dS m(-1) level of salinity, but these characters were found to decrease slowly in tolerant genotypes.

Single-level cervical radiculopathy: clinical outcome and cost-effectiveness of four techniques of anterior cervical discectomy and fusion and disc arthroplasty

Although there are several accepted methods of surgical treatment for single-level cervical radiculopathy, the choice depend on the surgeon's preference. The techniques may vary in peri-operative morbidity, short- and long-term outcome, but no study so far has analyzed their cost-effectiveness. This study might give some insight in balancing cost and effectiveness and deciding the right technique. Sixty consecutive patients (15 each group), mean age 36 (range 24-76 years) with single-level cervical disc disease underwent surgical treatment with four different techniques in two centers over the period of 1999-2005. The four groups were--(1) plate and tricortical autograft, (2) plate, cage, and bone substitute, (3) cage only, and (4) disc arthroplasty. The data was collected prospectively according to our protocol and subsequently analyzed. The clinical outcome was assessed comparing visual analog scale (VAS) of neck pain and, short form 12 (SF12) questionnaire both pre- and postoperatively. The radiological assessment was done for fusion rate and postoperative related possible complications at 3 months, 6 months, 1 year, and final follow-up. The cost analysis was done calculating the operative time, hospital stay, implant cost together. The mean follow-up period was 31 months (range 28-43 months). The clinical outcome in terms of VAS of neck and arm pain and SF12 physical and mental score improvement (P=0.001) were comparable with all four techniques. The radiological fusion rate was comparable to current available data. As the hospital stay was longer (average 5 days) with plate and autograft group, the total cost was maximum (average 2,920 pound sterling) with this group. There was satisfactory clinical and radiological outcome with all four techniques. Using the cage alone was the most cost-effective technique, but the disc arthroplasty was comparable to the use of cage and plate. Anterior cervical discectomy and fusion is an established surgical treatment for cervical radiculopathy. Single-level cervical radiculopathy was treated with four different techniques. The clinical outcome and cost-effectiveness were compared in this study.

Primary tumours of the synovium. A report of four cases of malignant tumour

Four patients who developed malignant synovial tumours are described; one with chondromatosis developed a synovial chondrosarcoma and three with pigmented villonodular synovitis developed malignant change. The relevant literature is discussed.

Primary atypical sacral meningioma--not always benign

We present a case of an atypical recurrent meningioma of the sacrum with pulmonary metastasis in a 31-year-old man. He presented with deep-seated buttock pain and urinary hesitancy for 3 months. MRI revealed a lesion occupying the central and left side of the sacral canal at the S1-S2 level. Surgical excision of the lesion via a posterior approach was undertaken, and the patient became symptom-free post-operatively. Histology confirmed atypical meningioma. Eight months later he re-presented with similar symptoms, and MRI confirmed local recurrence. The patient underwent left hemisacrectomy. Six months later he again presented with low back pain and MRI confirmed a second local recurrence. A CT scan of the chest showed multiple lung metastases. The patient died of a severe chest infection 18 months later.

Familial chordoma

We have treated 175 patients with a chordoma over a ten-year period. Only two had a family history of the condition and we describe these in this paper. In one patient the tumour was at the craniocervical junction and in the other the lesion affected the sacrum. We have undertaken a literature review of familial chordoma and have identified chromosomal abnormalities associated with the condition.