A comparison of anterior knee pain, kneeling pain and functional outcomes in suprapatellar versus infrapatellar tibial nailing

Chronic knee pain following infrapatellar/suprapatellar magnetic intramedullary lengthening nails versus external fixators in limb length discrepancy: A retrospective review

Aims & objectives

Prior to the popularization of magnetic intramedullary nails (MILNs), gradual deformity correction using external fixation was the norm in limb lengthening. Trauma literature has shown MILN via a suprapatellar approach (SP) to be associated with less knee pain than either an infrapatellar entry (IP) or external fixation. Yet, no research has investigated chronic knee pain and MILNs. We assessed differences in chronic knee pain following lengthening via an IP or SP approach with an MILN versus external fixation.

Materials & methods

We reviewed 147 limbs (55 MILN/IP, 22 MILN/SP, 71 external fixator) in 124 patients who underwent tibial lengthening with ≥12 months follow-up between February 2012 and July 2020. Knee pain was assessed pre- and postoperatively at 6 and 12 months, with the Lysholm Knee Scoring Scale (LKSS) and numeric pain scale (0-10). Differences in knee pain outcomes were compared across methods, with subgroup analysis of MILN/SP and MILN/IP.

Results

Mean LKSS was 96.3 for external fixation and 88.5 for MILN (P = .011). In the MILN subgroups, mean LKSS was 91.7 for IP and 85.3 for SP. The IP group reported a lesser mean pain score (0.6 versus 2.1) at 12 months. Bilateral nail recipients demonstrated no knee pain differences versus unilateral. At 12 months postoperative, external fixation had better knee outcomes.

Conclusion

Tibial lengthening with external fixation was associated with less chronic anterior knee pain and better functional outcomes than MILN overall. In terms of MILN approach, IP surpassed SP on subjective pain scores. Larger tibial lengthening and knee pain studies are warranted.

Is there a trend towards semi-extended knee positioning during intramedullary tibial nailing in Latin America? A survey among 990 orthopaedic surgeons

OBJECTIVE

The aim of this study was to evaluate the Latin American orthopaedic trauma surgeons preference regarding knee positioning and entry portals for IM nailing and identify the reasons of these preferences.

METHODS

Using the AO Trauma database, 22.285 surveys were distributed by email to Latin American orthopaedic surgeons. Demographic data and practice patterns, especially regarding knee positioning and approach for tibial nailing, were then evaluated and statistically treated.

RESULTS

amongst one thousand five hundred fourteen responses, 990 orthopaedic surgeons (4.4% of response rate) fully responded to the survey. Transpatellar tendon approach (613 / 61.9%,) with the knee in flexion (518 / 52.3%) on a radiolucent table remains the standard practice for intramedullary tibial nailing. Even for proximal and distal tibial nailing, the transpatellar tendon approach (455 / 46%) with the knee in flexion (562 / 56.8%) hold on the most used method. Only 55 (9.36%) orthopaedic surgeons reported that they have migrated to the supra-patellar tibial nailing in the recent years. The main reasons for a low rate of migration were lack of knowledge about the technique and unavailability of specific gigs and cartilage protectors for a safe suprapatellar nailing.

CONCLUSION

Even with the potential benefits of the semi-extended knee positioning for tibial nailing, the Latin American orthopaedic community remains using the transpatellar tendon approach with the knee in flexion as the standard technique. Lack of surgical training for suprapatellar and parapatellar approaches with the knee in semi-extension, added by the unavailability of suprapatellar jigs and soft outer protection sleeves contribute to counter the trend towards the semi-extended techniques.

Suprapatellar Tibial Nailing: Future or Fad?

Over the last hundred years, there have been significant advancements in the way the Orthopaedic community treats tibial fractures. More recently, the focus of Orthopaedic trauma surgeons has been comparing the different techniques of insertion for tibial nails, specifically suprapatellar (SPTN) versus infrapatellar. The existing literature is convincing that there does not appear to be any clinically significant differences between suprapatellar and infrapatellar tibial nailing, with some apparent benefits of SPTN. Based on the current body of literature and our personal experience with SPTN, we believe the suprapatellar tibial nail will become the future for most tibial nailing procedures, regardless of fracture pattern. We have seen evidence of improved alignment in both proximal and distal fracture patterns, decreased radiation exposure and operative time, relaxation of the deforming forces, ease of imaging, and static positioning of the leg, which would be helpful for the unassisted surgeon, as well as no difference in anterior knee pain or articular damage within the knee between the two techniques.

Tibial Intramedullary Nailing by Suprapatellar Approach: Is It Quicker and Safer?

Background

With the increasingly accepted method of suprapatellar tibial nailing for tibial shaft fractures, we aimed to compare intraoperative and postoperative outcomes of infrapatellar (IP) vs suprapatellar (SP) tibial nails.

Methods

This is a retrospective cohort analysis of 34 SP tibial nails over three years vs 24 IP tibial nails over a similar time frame. We compared total radiation dose (TRD), patient positioning time (PPT), fracture healing and follow up time. Knee pain in the SP group was evaluated utilising the Hospital for Special Surgery (HSS) Knee Injury and Osteoarthritis Outcome Score (KOOS).

Results

Fifty-eight patients with a mean age of 43 years were included. Mean intraoperative radiation dose for SP nails was 61.78 cGy (range: 11.60-156.01 cGy) vs 121.09 cGy (range: 58.01-18.03 cGy) for IP nails (p < 0.05). Mean PPT for SP nails was 10 minutes vs 18 minutes for IP nails (p < 0.05). All fractures united in the SP group vs one non-union in the IP group. Mean follow up was 5.5 months vs 11 months in the IP and SP groups, respectively. Mean KOOS was 7 (range: 0-22) at six months for the SP group.

Conclusion

The semi-extended position (SP group) leads to reduced TRD because of ease of imaging. Patients showed improved outcomes with shorter follow up and fracture union in all patients (SP group). The KOOS revealed that SP nail patients had minimal pain and good knee function. This study establishes a management and patient-reported outcome measures (PROMs) baseline for ongoing evaluation of SP nails.

Visualising knee loading patterns during kneeling and the development of a laboratory-based adaptation of the Aberdeen Weight-Bearing Test (Knee)

BACKGROUND

Information regarding the loading of key anatomical structures of the knee during kneeling would enhance existing functional tests, yet current visualisation methods are limited and require further development.

AIMS

(1) Develop a knee loading visualisation technique to investigate loading patterns of the knee during kneeling; and (2) determine the utility of the technique in combination with vertical ground reaction forces and centre of pressure data in the lab-based Aberdeen Weight-Bearing Test (Knee) by assessing their reliability.

METHODS

Fourteen healthy participants conducted kneeling tasks with and without knee pads across two testing sessions. Eight force-sensitive resistors were affixed to the right knee throughout different kneeling tasks: upright kneeling, and reaching forward, back, left, and right. A photo of the force-sensitive resistor configuration was used to generate participant-specific heat maps of knee loading. Two in-ground force platforms were used to measure vertical ground reaction forces and centre of pressure.

RESULTS

The inferior patella tendon showed the highest proportion of activation during both bare and knee pad kneeling for all kneeling tasks. Knee pads reduced the repeatability of knee loading patterns. Force-sensitive resistor activation and vertical ground reaction force components of the lab-based Aberdeen Weight-Bearing Test (Knee) were shown to be reliable, whereas the centre of pressure data was unreliable.

CONCLUSION

We have developed a lab-based technique for visualising knee loading using force-sensitive resistors. The combination of force-sensitive resistor activation and vertical ground reaction force data provides valuable insights into both the magnitude and locations of applied loads throughout kneeling.

Investigating and defining outcomes of suprapatellar versus infrapatellar intramedullary nailing of tibial shaft fractures: a protocol for a pilot randomised controlled trial

Background

Anterior knee pain is often reported following intramedullary nailing of tibial shaft fractures. The aetiology remains unclear, but the surgical approach may play an important role. To date, no biomechanically validated method exists to assess patient outcomes specific to anterior knee pain in this cohort. The central aims of this study are to (1) evaluate the feasibility of a full-scale randomised controlled trial (RCT) investigating the influence of surgical approach on intramedullary nailing of tibial shaft fractures (suprapatellar versus infrapatellar nailing), (2) explore differences in clinical outcomes between the approaches, and (3) explore the development of a biomechanically validated methodology for assessing post-operative anterior knee pain and knee function specific to intramedullary nailing of tibial shaft fractures.

Methods

This pilot study will follow a prospective randomised controlled design at the Royal Adelaide Hospital and The Queen Elizabeth Hospital (South Australia). This study aims to recruit 60 patients between 18 and 60 years old who will be randomly assigned to either the suprapatellar or infrapatellar approach following a decision for intramedullary surgical fixation by the treating surgeon. All nails in this study will be Stryker T2 Alpha nails. Patients will undergo standard radiograph, magnetic resonance imaging, and clinical assessments in-line with their standard operative care, and complete a number of patient-reported and performance-based outcome measures. Performance-based outcome measures will be assessed utilising three-dimensional motion capture techniques. Follow-up time points are 3, 6, 12, and 18 months. Feasibility outcomes include ability to meet enrolment and retention metrics, compliance with all questionnaires and assessment procedures, and the occurrence of any adverse events. The primary clinical outcome is the incidence of anterior knee pain at 12 months after surgery.

Discussion

This study will establish the feasibility and inform the design of a large-scale RCT. Evaluation of all clinical data and patient outcomes will lead to the development of a new tool for assessing patient outcomes in this cohort. Limitations of the study include an unpredictable enrolment rate and loss to follow-up, small sample size, and the unknown ability of three-dimensional motion analysis to pick up the effects of anterior knee pain after tibial nailing.

Trial registration

This trial was prospectively registered on the 7 February 2020 on ANZCTR, ACTRN12620000109909.