The retropatellar portal as an alternative site for tibial nail insertion: a cadaveric study

Comparative analysis of the parapatellar and subpatellar approaches in reducing peripheral knee pain post-intramedullary tibial fracture surgery

INTRODUCTION

Intramedullary tibial nailing is a standard treatment for tibial shaft fractures. Postoperative knee pain significantly impacts functional recovery; however, studies on this issue are limited. This study evaluated the effect of the parapatellar approach for intramedullary nailing on postoperative knee pain.

MATERIALS AND METHODS

A total of 29 patients with tibial shaft fractures treated with intramedullary nails from March 2019 to January 2022 were divided into two groups based on the surgical approach: the semi-extended lateral parapatellar approach and the conventional subpatellar ligament split approach. Recorded metrics included operation time, intraoperative fluoroscopy count, intraoperative bleeding volume, Visual Analog Scale (VAS) scores for knee pain at 24 h, 72 h, 1 week, and 1 month postoperatively, fracture healing time and Lysholm knee functional scores at 12 months.

RESULTS

Both groups completed the operation without significant differences in operation time, intraoperative bleeding, fracture healing time, or intraoperative fluoroscopy (P > 0.05). The parapatellar group showed significantly better VAS scores for knee pain at 24 h, 72 h, and 1 week postoperatively compared to the control group (P < 0.05), with no significant difference at 1 month. After 12 months, Lysholm scores indicated no significant differences in knee support, locking, and swelling (P > 0.05); however, the parapatellar group showed significant improvements in lameness, instability, stair climbing, squatting, and pain (P < 0.05). Overall, the parapatellar group outperformed the control group (P = 0.01). Additionally, long-term follow-up revealed potential advantages of the parapatellar approach in improving long-term functional outcomes.

CONCLUSIONS

Using the parapatellar approach for tibial intramedullary nailing avoids splitting the patellar ligament and entering the joint cavity, minimizing knee joint impact and effectively reducing postoperative knee pain, with potential benefits in long-term functional recovery.

The Lateral Para-Patellar Approach for Intramedullary Tibia Nailing in Distal Tibia Extra-articular Fractures: A Prospective Cohort Study

BACKGROUND AND OBJECTIVES

 The treatment of extra-articular distal tibia fractures is still a subject of debate and frequently necessitates surgical treatment, and intramedullary nailing (IMN) offers a minimally invasive approach with excellent results. Important factors in these procedures are positioning, operative duration, and radiation exposure. This study details the semi-extended lateral para-patellar approach for IMN of distal tibia extra-articular fractures and documents our findings regarding operative time, intra-operative radiation exposure, residual anterior knee pain, knee functional and radiological outcomes at six months follow-up.

METHODS

We reviewed the cases of 60 patients who underwent IMN for distal tibia extra-articular fractures from May 2022 to March 2024, employing an extra-articular lateral para-patellar approach in the semi-extended position. Patients were evaluated clinically and radio-graphically for a minimum follow-up period of six months. Data collected included duration of surgery, intraoperative radiation exposure, and knee functional score for all patients. Assessment of fracture healing, residual deformities, residual anterior knee pain, and range of motion of the treated knee compared to the contralateral knee was done at a six-month follow-up.

RESULTS

The average surgery duration was 54 ± 5 minutes, with intraoperative imaging averaging 48 exposures. The average time to union was 16 ± 3 weeks. Six months post-surgery, the mean Knee Society Score was 86.4 ± 3.5 (out of 100). At the six months follow-up, all patients exhibited clinical and radiographic healing, with only two cases showing mal-alignment (angular deformity <10 degrees). All patients regained a comparable range of motion in their knees.

CONCLUSIONS

The semi-extended lateral para-patellar approach for nailing of distal tibia extra-articular fractures enhances reduction, simplifies nail insertion, reduces both fluoroscopy and operative time, minimizes anterior knee pain and improves knee functional outcomes at six months follow-up.

A Suprapatellar Approach, When Compared With an Infrapatellar Approach, Yields Less Anterior Knee Pain and Better Patellofemoral Joint Function, for Intramedullary Nailing of Diaphyseal Tibial Fractures: Results of a Randomized Controlled Trial

OBJECTIVES

To assess if a suprapatellar (SP) approach, when compared with an infrapatellar (IP) approach, yielded less patient-reported anterior knee pain and higher patellofemoral joint function at 6 weeks and 12 months postoperatively, when treating tibial fractures with intramedullary nailing.

METHODS

DESIGN

Prospective, parallel-group randomized control trial.

SETTING

Tertiary level 1 trauma care center, Brisbane, Australia.

PATIENTS SELECTION CRITERIA

Skeletally mature patients with an acute diaphyseal tibial fracture (AO/OTA 41A2/3, 42 A1-43A3) amenable to an intramedullary nailing were included. Exclusion criteria were periprosthetic fractures, nonunions, and presence of a contralateral injury that would restrict weight-bearing.

OUTCOME MEASURES AND COMPARISONS

Anterior knee pain through the visual analog scale (VAS) and patellofemoral function using the Kujala scale at 6 weeks and 12 months were compared between those treated with a SP and IP approach.

RESULTS

Ninety-five tibia fractures were included in the randomized trial, with complete follow-up data for 44 and 46 tibia fractures in the SP and IP groups, respectively. The SP cohort exhibited better patellofemoral knee function at both 6 weeks (Kajula 53.0 for SP vs. 43.2 for IP, P < 0.01) and 12 months (Kujala 92.0 for SP vs. 81.3 for IP, P < 0.01) postoperatively and a reduction in anterior knee pain at 12 months postoperatively (VAS 0.7 SP vs. 2.9 IP, P < 0.01).

CONCLUSIONS

This randomized trial demonstrated clinically meaningful differences in patellofemoral function, for a SP versus IP approach, with a greater than 10 point discrepancy in Kujala score at both 6 weeks and 12 months. In addition, there was a clinically important difference in VAS knee pain scores for patients at 12 months, but not at 6 weeks, postoperatively. These results contribute to the growing body of evidence demonstrating the functional and clinical benefits of the SP approach.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Cartilaginous defect of the lateral trochlea following suprapatellar nailing of an open tibial shaft fracture: a case report

A 34-year-old female sustained a 1.8 cm full-thickness chondral defect of the right lateral trochlear surface as the result of intramedullary tibial nailing via a suprapatellar portal to treat a displaced right sided open comminuted spiral fracture of the distal tibial shaft. An osteochondral allograft was used to treat the chondral defect. Iatrogenic injury to intraarticular structures is a potential complication when inserting a tibial nail via a suprapatellar portal. Using proper technique with cannula systems and guide pins is essential to lowering the risk of damage to intraarticular structures.

Suprapatellar versus infrapatellar approach for intramedullary nail fixation of tibial shaft fractures: a review of the literature

Semi-extended suprapatellar intramedullary nail fixation of tibial fractures has recently been gaining popularity. Several recent studies and meta-analyses compare the outcomes of the suprapatellar approach with the traditional infrapatellar approach. Despite concerns with intra-articular placement of instruments, studies show the suprapatellar approach to be a safe alternative. Several articles conclude that the suprapatellar approach may be superior to the infrapatellar approach. This review discusses recent findings comparing suprapatellar and infrapatellar approaches for nail insertion.

Retro-patellar approach in telescopic nailing of the tibia in children with osteogenesis imperfecta

PURPOSE

Telescopic intramedullary nailing (TN) has become the main choice of treatment in children with osteogenesis imperfecta (OI). The classical parapatellar tibial nailing technique poses difficulties in maintaining reduction, insertion of the nail and fluoroscopic imaging. Also, deformities of the proximal tibia in relatively small children with OI can be problematic for tibial nailing. In this report, we present the retro-patellar approach in tibial TN of children with OI as an alternative to the classical approach and report the early radiographic and clinical results of our patients.

METHODS

The nail is inserted through a skin incision proximal to the patella, passing inside the patellofemoral joint while the knee is positioned to 15° to 20° of flexion. In total, 30 tibiae of 15 patients had been operated and were reviewed after at least one year of follow-up. Any complications, such as implant failure, joint damage or instability, malunion, nonunion or refracture, were recorded.

RESULTS

The mean age of our patients was 8.5 years, and the mean follow-up period was 27 months. There were no complaints involving the knee. All patients showed complete union without any implant failure or refracture. We did not observe any nail protrusion, bending or loss of correction during the procedure.

CONCLUSION

The retro-patellar approach for tibial TN appears to be safe and effective in patients with OI.

LEVEL OF EVIDENCE

IV.

Difference in Pain, Complication Rates, and Clinical Outcomes After Suprapatellar Versus Infrapatellar Nailing for Tibia Fractures? A Systematic Review of 1447 Patients

OBJECTIVES

To assess the effectiveness of suprapatellar (SP)-nailing versus infrapatellar (IP)-nailing of tibia fractures in anterior knee pain, complications (retropatellar chondropathy, infection, and malalignment) and physical functioning and quality of life. A clinical question-driven and thorough systematic review of current literature is provided.

DATA SOURCE

PubMed and Embase databases were searched for studies published between 2010 and 2020 relating to SP and IP-nailing of tibia fractures. The study is performed in concordance with PRISMA-guidelines.

STUDY SELECTION

Studies eligible for inclusion were randomized controlled trials, prospective and retrospective observational studies reporting on outcomes of interest.

DATA EXTRACTION

Data extraction was performed independently by 2 assessors. Methodological quality and risk of bias was assessed according to the guidelines of the McMaster Critical Appraisal.

DATA SYNTHESIS

Continuous variables are presented as means with SD and dichotomous variables as frequency and percentages. The weighted mean, standardized weighted mean differences, and 95% confidence interval were calculated. A pooled analysis could not be performed because of differences in outcome measures, time-points, and heterogeneity.

RESULTS

Fourteen studies with 1447 patients were analyzed. The weighted incidence of anterior knee pain was 29% after SP-nailing and 39% after IP-nailing, without reported significance. There was a significant lower rate of malalignment after the SP-approach (4% vs. 26%) with small absolute differences in all planes. No substantial differences were observed in retropatellar chondropathy, infection, physical functioning, and quality of life.

CONCLUSIONS

This systematic review does not reveal superiority of either technique in any of the respective outcomes of interest. Definitive choice should depend on the surgeon's experience and available resources.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

The use of 'blocking' screws for the 'closed' reduction of difficult proximal and distal femoral fractures

Most meta-diaphyseal femoral fractures that are treated with intramedullary nailing can be reduced satisfactorily by skeletal traction without ‘opening’ the fracture site and therefore, complications such as nonunion, infection and wound healing problems are reduced.

In cases where adequate fracture reduction cannot be achieved by skeletal traction, ‘reduction aids’ have been used during the operative procedure in order to avoid the exposure of the fracture site.

The ‘blocking’ screw, as a reduction tool, was proposed initially for the ‘difficult’ metaphyseal fractures of the tibia. Subsequently, surgeons have tried to implement the ‘blocking’ screw technique in ‘difficult’ distal femoral fractures.

This article presents the ‘blocking’ screw technique as an adjunctive process in the management of fractures of the proximal and distal femur which are found to be non-reducible by skeletal traction alone. The minimal invasiveness of the technique contributes greatly to the preservation of both the soft tissue integrity and the fracture haematoma and thus reduces the major complications that can occur by exposing the fracture site.

Cite this article: EFORT Open Rev 2021;6:451-458. DOI: 10.1302/2058-5241.6.210024

The Influence of Sagittal Proximal Tibial Anatomy in Tibial Intramedullary Nailing

OBJECTIVES

To quantify anatomic variation in sagittal proximal tibial anatomy and determine if anatomy or nail insertion method influences the radiographic nail position.

DESIGN

Retrospective cohort of prospectively collected data.

SETTING

Level 1 trauma center.

PATIENTS/PARTICIPANTS

Forty-five patients with 46 tibia fractures (OTA/AO 41A, 42, and 43) treated with infrapatellar (IP) or suprapatellar (SP) nailing. The average patient age was 40.6 years (range 19-62 years).

INTERVENTION

Patients received IP or SP nailing. Cohorts were analyzed based on the nailing technique and proximal tibial anatomy.

MAIN OUTCOME MEASUREMENTS

Proximal tibial radiographic anatomy was quantified using novel measurements [anterior tubercle angle (ATA) and entry point position (EPP)]. Nail entry point, entry point displacement after reaming, nail position, and quality of reduction was measured and compared between groups.

RESULTS

ATA was highly variable between patients. ATA was strongly correlated with EPP with a higher ATA associated with EPP more colinear with the intramedullary canal. Patients with low ATA treated with IP nailing had significantly longer operative times (60.0 vs. 45.7 minutes). Low ATA tibias had a higher incidence of entry point displacement due to eccentric reaming compared with high ATA tibias (70% vs. 38%) with the highest incidence of entry point displacement and absolute displacement in low ATA tibias treated with IP nailing (86%, 2.8 mm). SP nailing demonstrated shorter operative times relative to IP nailing (45.5 vs. 55.6 minutes).

CONCLUSIONS

There is considerable variability in proximal tibial anatomy and these features influences the nail position within the tibia. These differences in anatomy should be considered to potentially reduce operative times, entry point displacement and anteriorization of tibial nails.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Supra-patellar nailing for isolated closed tibial shaft fractures: Medium term functional outcomes from an Academic Level 1 Trauma centre

Aims The aim of this study was to assess functional outcome, at medium-term follow up, in patients undergoing intra-medullary nailing of tibial shaft fractures, using the supra-patellar approach. Materials and methods The study included patients with intra-medullary nailing, for diaphysial tibia fractures, between March 2013 to August 2015. An initial audit compared short-term functional outcomes at 15 months, between the supra and infra-patellar approaches, using a cohort of 20 patients (10 in each group). Subsequently, a larger cohort of 22 patients with supra-patellar nailing, were reviewed for medium term assessment of their functional outcomes at average 60 months (50 - 78 months) and the results between all 3 groups were compared. All patients were assessed using the Kujala and Oxford Knee Scores. Results The mean age of the cohorts was 38 years (18-87years). The mean follow-up was 15 months for the initial audit and 60 months for the medium-term results. The initial audit showed that the supra-patellar group had statistically significantly better Oxford and Kujala scores when compared to infra-patellar group (p < 0.05). At 5 years following supra-patellar nailing, the medium-term cohort showed improved outcome scores compared to the infra-patellar group at 1 year (p < 0.01) but showed no difference with the supra-patellar group at 1 year (p value >0.1). Conclusion Our study suggests that patients undergoing supra-patellar tibial nailing have better outcomes at 15 months compared to traditional infra-patellar nailing and more importantly, they continue to do well even at 5 years, despite perceived risks associated with this technique.

Semiextended Tibial Nail Insertion Using an Extraarticular Lateral Parapatellar Approach: A 24-Month Follow-up Prospective Cohort Study

OBJECTIVE

To analyze the outcomes of tibial shaft fractures treated with a lateral parapatellar approach in the semiextended position for intramedullary nail insertion.

DESIGN

Prospective cohort study.

SETTING

Level I trauma center.

PATIENTS AND METHODS

Seventy patients treated from March 2012 to July 2015 with intramedullary nailing (IMN) using an extraarticular lateral parapatellar approach in the semiextended position were reviewed. Patients were clinically and radiographically checked at a minimum follow-up of 24 months, and the following data were recorded: fracture healing, any residual deformity, nail-apex distance, range of motion of the treated knee together with the contralateral side, knee functional outcome, and residual knee pain.

RESULTS

Twenty-four months after surgery, all patients were clinically and radiographically healed, with 2 cases of malalignment (angular deformity <10 degrees). The average range of motion of the treated knee was 0-130.6 degrees (±8.6 degrees) compared with 0-131.1 degree (±7.9 degrees) of the contralateral. Lysholm knee score was excellent for 57 patients, good for 11, and fair for 2. The mean residual pain was 0.6 (±1.1) according to the visual analogue scale.

CONCLUSIONS

The described technique represents an effective option for IMN of tibial fractures. It is suitable for all tibial fractures, including proximal and distal. The results of our series demonstrate the effectiveness of this technique with nearly complete recovery of knee function and negligible incidence of anterior knee pain at a minimum follow-up of 24 months.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

[Reduction techniques in intramedullary nailing osteosynthesis]

Intramedullary nailing was originally conceived for the stabilization of shaft fractures of long bones. Due to new nail designs and multiple interlocking possibilities, the spectrum of nailing has significantly increased. Nailing of fractures beyond the isthmus is technically challenging because fractures need to be reduced before the nailing procedure starts. Indirect techniques of reduction include the use of an extension table, a large distractor or an external fixator. Direct reduction with pointed reduction forceps, lag screws, a cerclage wire or a short plate can optimize indirect reduction. The choice of the correct entry portal is of utmost importance for an optimal operative result. The location of the entry portal is dependent on the local anatomy and the bend of the nail. The optimal entry portal at the proximal tibia is directly behind the patellar tendon and accessible with the knee in more than 90° of flexion, alternatively through a suprapatellar approach with a slightly flexed knee joint. Insertion of the nail through the suprapatellar approach is possible without stress on the reduced fracture fragments. Blocking screws create an artificial isthmus in the metaphyseal area and force the guide wire in the desired direction. Blocking screws help to avoid axial malalignment during nail insertion. Interlocking of the nail with screws coming from different directions prevents secondary dislocation.

A meta-analysis of suprapatellar versus infrapatellar intramedullary nailing for the treatment of tibial shaft fractures

Background

Whether the optimal treatment for tibial shaft fractures is suprapatellar intramedullary nailing or infrapatellar approach is controversial.

Materials and methods

PubMed, Embase, Cochrane, Web of science and CNKI, Wan fang Chinese databases were retrieved from their establishment to April 26, 2017. Seven studies (three randomized and four clinical controlled trials) were included in the final analysis. This meta-analysis included 683 patients with tibial shaft fracture (suprapatellar: 341; infrapatellar: 342).

Results

There was significant difference between suprapatellar and infrapatellar approach surgery in the incidence of knee pain (P = 0.003). The malalignment of the sagittal and coronal plane in suprapatellar surgery was more serious than in the infrapatellar approach (sagittal plane: P < 0.00001; coronal plane:P = 0.07). The infrapatellar approach surgery was more time-consuming than suprapatellar surgery (P = 0.01), with no significant difference in knee function score (P = 0.35).

Conclusions

Suprapatellar intramedullary nailing reduced the incidence of knee pain and the average malalignment of fractures compared to infrapatellar intramedullary nailing. It also reduced the operation time and fluoroscopy time. The results of the study should be interpreted with caution due to the heterogeneity of the study designs.

Improved Outcomes With Semi-extended Nailing of Tibial Fractures? A Systematic Review

OBJECTIVE

To systematically review the existing literature to determine whether knee pain and function following intramedullary nailing of tibial shaft fractures differs significantly by surgical technique-specifically with semi-extended nailing versus traditional infrapatellar approaches.

DATA SOURCE

A comprehensive search of PubMed/MEDLINE, EMBASE, and the Cochrane Database was conducted on August 15, 2018.

STUDY SELECTION

We included level I-level III studies that examined outcomes of tibial intramedullary nailing utilizing a semi-extended technique. All included studies reported Lysholm Knee Scores with minimum clinical follow-up of 1 year. Non-English language literature and studies older than 20 years were not included.

DATA EXTRACTION

Data from each study were independently recorded by 2 reviewers.

DATA SYNTHESIS

Two prospective, randomized trials and 4 retrospective cohort studies were included in this review. A meta-analysis was not performed.

CONCLUSIONS

Evidence comparing postoperative knee pain and functional outcomes between semi-extended and traditional infrapatellar nailing is limited. Available literature suggests satisfactory outcomes with semi-extended nailing. The highest level of evidence available does indicate improved pain and function with semi-extended nailing as compared to infrapatellar nailing. Additional research may be required to reach consensus conclusions.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Importance of Mechanoreceptors and Other Neural Structures Within the Anterior Intermeniscal Ligament in the Etiology of Anterior Knee Pain After Tibial Nailing

BACKGROUND

Anterior knee pain is the most common complication after intramedullary tibial nailing. The cause is often multifactorial and varies among individuals. Violation of the anterior intermeniscal ligament (AIL) during intramedullary tibial nailing might be a possible source of postsurgical anterior knee pain. Although there is a certain ambiguity regarding the importance and function of the AIL, neural structures in the AIL tissue might play a significant role with respect to functional purposes and pain perception.

METHODS

We subjected 6 AIL specimens to histologic examination to identify the neural structures that are a mandatory requirement as a source of anterior knee pain. Specifically, we performed three-dimensional immunohistochemical investigation of subtyping, orientation, and detailed characterization of neural structures within the AIL tissue.

RESULTS

Histologic and three-dimensional immunohistochemical examinations confirmed the presence of neural structures in all 6 AIL specimens. We identified myelinated and unmyelinated nerve fibers, as well as all types of mechanoreceptors.

CONCLUSIONS

Free nerve endings are a mandatory requirement for pain perception as a result of AIL violation during tibial nailing. Our verification of all different types of mechanoreceptors in the AIL tissue makes a role of the ligament in knee joint function and proprioception highly probable. Further investigations are necessary to clarify possible correlations between neural supply and function of the AIL. Violation of the ligament during operative procedures should be avoided, although the significance of the AIL is still debated.

Anterior intermeniscal ligament: frequency in MRI studies and spatial relationship to the entry point for intramedullary tibial nailing related to the risk of iatrogenic violation

BACKGROUND

Anterior knee pain is the most common complication after intramedullary tibial nailing. Often, the cause is multifactorial and individually different. Violation of the anterior intermeniscal ligament (AIL) during intramedullary tibial nailing might be a possible origin of postsurgical anterior knee pain. Both the importance and function of the AIL remain somewhat ambivalent, and even the figures quoted in the literature for its existence in the population vary drastically. Our aim was to verify the estimated frequency of the AIL in the literature by retrospectively analysing the data of MRI studies conducted at our hospital. In addition, we attempted to assess the potential risk of AIL violation during intramedullary tibial nailing, based on the spatial arrangement.

METHODS

Two independent examiners analysed the images generated in 351 MRI studies conducted at our hospital between June 2013 and May 2014. All cases who did not reveal any previous knee-joint injury or osteoarthritis of the knee were allocated to group I. All other cases were included in group II. To estimate the potential risk of AIL injury during the nailing procedure, the distance between the AIL and the theoretical entry point for intramedullary nailing was measured.

RESULTS

We identified the AIL on the images of nearly all patients (96.5%) in group I. In group II, the presence of the AIL was confirmed in only 51.4% of cases (p < 0.001). The average distance between the AIL and theoretical entry point for intramedullary tibial nailing was 10.1 mm (range 3.48-18.88 mm).

CONCLUSIONS

Because we were able to confirm the presence of the AIL in nearly all patients without a history of knee joint injuries or osteoarthrosis, we presume that the AIL may play a role in knee joint function. Violation of the AIL during intramedullary nailing appears likely due to the close position of the AIL in relation to the entry point for the inserted nail. As a result and due to its rich sensory innervation, a connection between AIL violation during tibial nailing and postoperative onset of anterior knee pain seems likely. To eliminate one risk factor of anterior knee pain development and in view of the unresolved issues of AIL function, violation of the ligament during any operative procedure should be avoided.

Risk of Knee Sepsis After Treatment of Open Tibia Fractures: A Multicenter Comparison of Suprapatellar and Infrapatellar Approaches

OBJECTIVES

The suprapatellar approach for medullary nailing of the tibia is increasing. This requires intra-articular passage of instruments, which theoretically places the knee at risk of postoperative sepsis in the setting of open fracture. We hypothesized that the risk of knee sepsis is similar after suprapatellar or infrapatellar nailing of open tibia fractures.

DESIGN

Retrospective, multicenter.

SETTING

Three urban level 1 trauma centers.

PATIENTS

All patients treated with medullary nailing for open diaphyseal tibia fractures (OTA 42) from 2009 to 2015. Patients younger than 18 years of age and with less than 12 weeks of follow-up were excluded. We identified 289 fractures in 282 patients.

INTERVENTION

Suprapatellar (SP) or infrapatellar (IP) medullary nailing of open tibia fractures.

MAIN OUTCOME MEASUREMENT

Occurrence of ipsilateral knee sepsis, defined as presence of a positive culture from knee aspiration or arthrotomy. Deep infection requiring operative debridement, superficial infection requiring antibiotic therapy alone, and all-cause reoperation were also recorded.

RESULTS

IP nailing was used for 142 fractures. There were 20 infections (14.1%), of which 14 (9.8%) were deep. Fourteen tibias (9.8%) required reoperation for noninfectious reasons for 28 total reoperations (19.7%). SP nailing was used in 147 fractures. There were 24 infections (16.2%), of which 16 (10.8%) were deep. Fourteen additional tibias (9.5%) required reoperation for noninfectious reasons for a total of 30 reoperations (20.4%). There were no differences in the rates of infection, deep infection, or reoperation between groups. There were 2 cases of knee sepsis after SP nailing (1.4%) but zero cases after IP nailing (P = 0.5).

CONCLUSIONS

There was no significant difference in the rate of knee sepsis with SP or IP approaches. The risk of knee sepsis after SP nailing of open fractures is low, but present.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Infrapatellar vs. suprapatellar approach to obtain an optimal insertion angle for intramedullary nailing of tibial fractures

BACKGROUND

During intramedullary nailing of tibial fractures, the insertion angle of the nail is of great importance. When the nail impacts the posterior cortex due to a large insertion angle with a dorsal target course, higher insertion forces are needed, and the danger of iatrogenic fractures increases. Accordingly, the insertion direction should be as parallel as possible to the longitudinal axis of the tibia. We aimed to confirm the hypothesis that intramedullary nailing of tibial fractures can be performed with smaller insertion angles via a suprapatellar approach rather than infrapatellar approach.

METHODS

In 19 human bodies of donors with intact tibiae, we performed intramedullary nailing by both a suprapatellar and an infrapatellar approach. The correct entry point was determined by fluoroscopy. Subsequently, the medullary canal was reamed up to a diameter of 10 mm, and a 9 mm polytetrafluorethylen tube was inserted instead of a tibia nail. The angle between the proximal aspect of the tube and the longitudinal axis of the tibia was measured using a computer-assisted surgery system.

RESULTS

The angle between the proximal aspect of the inserted tube, simulating the tibial nail, and the longitudinal tibial axis was significantly larger when using the infrapatellar approach.

CONCLUSIONS

We achieved an insertion angle significantly more parallel to the longitudinal axis when using a suprapatellar approach for intramedullary nailing of tibial fractures. Thereby, both the risk of iatrogenic fracture of the posterior cortex and apex anterior angulation of the short proximal fragment can be reduced during intramedullary nailing of tibial fractures.

Semiextended approach for intramedullary nailing via a patellar eversion technique for tibial-shaft fractures: Evaluation of the patellofemoral joint

Intramedullary nail fixation is a common treatment for tibial-shaft fractures, and it offers a better functional prognosis than other conservative treatments. Currently, the primary approach employed during intramedullary nail insertion is the semiextended position is the suprapatellar approach, which involves a vertical incision of the quadriceps tendon Damage to the patellofemoral joint cartilage has been highlighted as a drawback associated with this approach. To avoid this issue, we perform surgery using the patellar eversion technique and a soft sleeve. This method allows the articular surface to be monitored during intramedullary nail insertion. We arthroscopically assessed the effect of this technique on patellofemoral joint cartilage. The patellar eversion technique allows a direct view and protection of the patellofemoral joint without affecting the patella. Thus, damage to the patellofemoral joint cartilage can be avoided.

Intramedullary Nailing with a Suprapatellar Approach and Condylar Bolts for the Treatment of Bicondylar Fractures of the Tibial Plateau

Background

Bicondylar tibial plateau fractures have been treated with either plating or external fixation techniques, with conflicting results. A recently introduced technique involving the combined use of intramedullary nailing via a suprapatellar approach and condylar bolts could represent a new pathway toward better treatment of this severe injury.

Methods

The present report describes a retrospective and prospective study of all 17 patients (age range, 25 to 75 years) who were admitted under the author's care for the treatment of a closed, bicondylar tibial plateau fracture between 2013 and 2015. All patients consented to undergo fixation of the fracture with intramedullary nailing through a suprapatellar approach and with use of condylar bolts. The reconstructed articular surface was supported with freeze-dried allograft that had been previously soaked in concentrated bone marrow. The patients were followed at regular intervals, and the results were assessed with the Knee injury and Osteoarthritis Outcome Score (KOOS).

Results

All patients were followed for at least 1 year (average and standard deviation, 25.23 ± 8.95 months; range, 12 to 46 months). All fractures united clinically and radiographically between 10 and 22 weeks (average, 15.1 ± 2.91 weeks), with no instances of neurovascular complication, infection, or implant failure. One patient underwent early revision of the fixation because of unsatisfactory reduction of the articular surface, and 1 patient had secondary fracture displacement. One condylar bolt was removed after fracture healing because of irritation at the insertion site. However, all patients regained knee motion without physiotherapy and all were fully weight-bearing by the fifth postoperative month.

Conclusions

The short and intermediate-term results associated with the use of the proposed technique appear to be satisfactory. However, the effectiveness of the technique should be reassessed with long-term studies as well as comparative studies involving other fixation techniques.

Level of Evidence

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

No Incidence of Postoperative Knee Sepsis With Suprapatellar Nailing of Open Tibia Fractures

OBJECTIVE

To evaluate the incidence of knee sepsis after suprapatellar (SP) nailing of open tibia fractures.

DESIGN

Retrospective; Setting: ACS level 1 trauma center.

PATIENTS/PARTICIPANTS

We reviewed 139 open tibia fractures that underwent SP nailing as definitive treatment over a 5-year period (January 1, 2011 to January 1, 2016). Most patients (90%, n = 126) underwent intramedullary nailing at the time of their initial surgery. We defined knee sepsis as intra-articular infection requiring operative debridement, either open or arthroscopically, within 1 month's time.

INTERVENTION

Open tibia fractures treated with an SP tibial nail.

MAIN OUTCOME MEASUREMENTS

Demographic data, fracture characteristics, Gustilo and Anderson classification of open fractures, and occurrence of knee sepsis.

RESULTS

In 139 open tibia fractures, there were no cases of knee sepsis in the 30 days after treatment with an SP intramedullary nail. Eighty-seven percent of our cohort had Gustilo and Anderson type II (41%) or type III (46%) open fractures. Most open fractures (83%) underwent primary wound closure during the index procedures. Twenty-five limbs (18%) had evidence of infection at the open fracture site of their open fracture necessitating operative intervention and/or antibiotics: none, however, developed knee sepsis.

CONCLUSIONS

Although the SP approach carries intra-articular risks, we found a low risk of knee sepsis using this technique in the treatment of open tibia fractures. Our data suggest that there is no greater risk of intra-articular infection using an SP portal as compared with an infrapatellar one.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Suprapatellar Intramedullary Nail Technique Lowers Rate of Malalignment of Distal Tibia Fractures

OBJECTIVES

To report on the immediate postoperative alignment of distal tibia fractures (within 5 cm of the tibial plafond) treated with suprapatellar intramedullary nail (IMN) insertion compared with the infrapatellar technique. Primary outcomes include alignment on both the anteroposterior and lateral radiographic views.

DESIGN

Retrospective cohort study.

SETTING

Two urban level I trauma centers.

PATIENTS

A total of 266 skeletally mature patients with a distal tibia fracture were treated with an IMN. One hundred thirty-two patients underwent this procedure through a suprapatellar technique.

INTERVENTION

Intramedullary nail placement.

MAIN OUTCOME MEASURES

Alignment.

RESULTS

The 2 treatment groups were evenly matched with respect to age, gender, fracture grade, and the presence of open fracture. Within the suprapatellar group, the fibula was intact, fixed, and remained fractured in 6 (4.5%), 22 (16.7%), and 104 (78.8%) cases, respectively. The fibula was intact, repaired, and remained fractured in 9 (6.7%), 32 (23.9%), and 93 (69.4%) cases, respectively, in the infrapatellar group. There was no difference in the rate of fibular fixation between the groups (P = 0.2). Primary angular malalignment of ≥5 degrees occurred in 35 (26.1%) patients with infrapatellar IMN insertion and in 5 (3.8%) patients who underwent suprapatellar IMN insertion (P < 0.0001).

CONCLUSIONS

This is the largest patient series directly comparing the suprapatellar with infrapatellar IMN insertion technique in the treatment of distal tibia fractures. In the treatment of distal tibia fractures, suprapatellar IMN technique results in a significantly lower rate of malalignment compared with the infrapatellar IMN technique.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Comparison between suprapatellar and parapatellar approaches for intramedullary nailing of the tibia. Cadaveric study

Intramedullary nailing is one viable option for treating fractures of the tibia with a short, proximal segment. For a procedure being carried out with the knee in a semi-extended position, either a suprapatellar or parapatellar approach may be used. The objective of this study is to demonstrate whether the entry point for tibia nails is obtainable through suprapatellar or parapatellar approaches and to evaluate the most frequent injuries of the knee with these two approaches.

MATERIALS AND METHODS

Paired legs from 10 fresh frozen cadavers were used. An arthroscopy was performed in each knee, documenting the status of the knee prior to the insertion of the tibia nail. In a random manner, the left or right leg underwent nailing with a suprapatellar or parapatellar approach in a semi-extended position. Fluoroscopy was utilized in each case to localize the entry point, and a tibia nail was inserted in all cases. A knee arthrotomy was then performed and the status of the following structures was assessed: patella and trochlea cartilage, tibia plateau cartilage, inter-meniscal ligament, lateral and medial meniscus, and the ACL.

RESULTS

The correct fluoroscopy entry point was achieved in all of the specimens (20). Three legs (3/10) with parapatellar approach had intra-articular disruption. In legs with a suprapatellar approach, patellar cartilage and trochlea cartilage damage was found in two of the specimens, respectively. There was one specimen with cartilage damage in the parapatellar approach. There were no meniscal injuries. Partial laceration of the intermeniscal ligament was found in three of the knees for each approach. One ACL injury was found in the suprapatellar group. Mean distance from the entry point to major structures is not significantly different with either approach. (p=0.45).

CONCLUSIONS

A good fluoroscopic entry point can be achieved using either the parapatellar or suprapatellar approach. The parapatellar approach for tibia nailing has similar rate of soft tissue damage compared to the suprapatellar approach. The suprapatellar approach damaged the cartilage in one-third of the cases and if cartilage injury occurs with the parapatellar approach, this is located in a low risk area.

Locked META intramedullary nailing fixation for tibial fractures via a suprapatellar approach

BACKGROUND

Intramedullary nailing is an effective approach for treatment of diaphyseal tibial fractures. However, infrapatellar intramedullary nailing can easily cause angulation and rotation displacement at the fracture ends and increase risk of postoperative infection. Intramedullary nailing via the suprapatellar approach was proved with good reduction and fixation. We used locked intramedullary nailing for the treatment of tibial fractures via a suprapatellar approach in this study.

MATERIALS AND METHODS

23 patients undergoing tibial fractures fixation by locked META intramedullary nailing via a suprapatellar approach were enrolled between June 2012 and October 2013. There were 18 males and 5 females. The average age was 35.5 years (range 18-60 years). The intraoperative data including operative time and blood loss and postoperative data consisting of hospital stays, fluoroscopy time, fracture healing time and complications were all recorded.

RESULTS

The average operative time, blood loss, fluoroscopy time and hospital stay were 78.2 ± 9.1 min, 90.4 ± 23.4 mL, 38.5 ± 6.5 s and 11 ± 3.4 days respectively. The mean followup period in all the patients was 15.5 months. Callus appeared in the patients at average 8 weeks after surgery. The mean knee and ankle range of motion were significantly improved at the last followup (P < 0.05). The average Hospital for Special Surgery and Olerud-Molander scores was 92 ± 4.3 points and 93.6 ± 3.9 points, respectively. No complications were observed.

CONCLUSION

Locked META intramedullary nail fixation via a suprapatellar approach is safe and effective for patients suffering from tibial fractures and earlier functional recovery.

Suprapatellar Versus Infrapatellar Tibial Nail Insertion: A Prospective Randomized Control Pilot Study

PURPOSE

The purpose of this OTA-approved pilot study was to compare the clinical and functional outcomes of the knee joint after infrapatellar (IP) versus suprapatellar (SP) tibial nail insertion.

DESIGN

Prospective, randomized.

SETTING

Level I trauma center.

METHODS

After institutional review board approval, skeletally mature patients with OTA 42 tibial shaft fractures were randomized into either an IP or SP nail insertion group after informed consent was obtained. The SP also underwent prenail and postnail insertion patella-femoral (PF) joint arthroscopy. Patients underwent follow-up (6 weeks, 3, 6, and 12 months) with standard radiographs, as well as visual analog score and pain diagram documentation. At the 6-month and 12-month visits, knee function questionnaires (Lysholm knee scale and SF-36) were completed. Magnetic resonance imaging/image (MRI) of the affected knee was obtained at 12 months. Ten patients in each group were required for a power analysis for the anticipated larger randomized control trial, but enrollment in each arm was not limited because of known problems with patient follow-up over a 12-month period.

RESULTS

A total of 41 patients/fractures were enrolled in this study. Of those, only 25 patients/fractures (14 IP, 11 SP) fully complied with and completed 12 months of follow-up. Six of 11 SP presented with articular changes (chondromalacia) in the PF joint during the preinsertion arthroscopy. Three patients displayed a change in the articular cartilage based on postnail insertion arthroscopy. At 12 months, all fractures in both groups had proceeded to union. There were no differences between the affected and unaffected knee with respect to range of motion. Functional visual analog score and Lysholm knee scores showed no significant differences between groups (P > 0.05). The SF-36v2 comparison also revealed no significant differences in the overall score, all 4 mental components, and 3/4 physical components (P > 0.05). The bodily pain component score was superior in the SP group (45 vs. 36, P = 0.035). All 11 SP patients obtained MRIs at 1 year. Five of these patients had evidence of chondromalacia on MRI. These findings did not correlate with either the prenail or postnail insertion arthroscopy. Importantly, no patient in the SP group with postnail insertion arthroscopic changes had PF joint pain at 1 year.

CONCLUSIONS

Overall, there seemed to be no significant differences in pain, disability, or knee range of motion between these 2 tibial intramedullary nail insertion techniques after 12 months of follow-up. Based on this pilot study data, larger prospective trial with long-term follow-up is warranted.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Suprapatellar nailing of tibial fractures-Indications and technique

Intramedullary nailing is the standard procedure for surgical treatment of closed and Gustilo-Anderson Grade I-II° open fractures of the tibial shaft. The use of intramedullary nailing for the treatment of proximal metaphyseal tibia fractures is frequently followed by postoperative malalignment, whereas plate osteosynthesis is associated with higher rates of postoperative infection. Intramedullary nailing of tibial fractures is generally performed through an infrapatellar approach. The injured extremity must be positioned at a minimum of 90° of flexion in the knee joint to achieve optimal exposure of the correct entry point. The tension of the quadriceps tendon causes a typical apex anterior angulation of the proximal fragment. The suprapatellar approach improves reduction of the fracture and reduces the occurrence of malalignment during intramedullary nailing of extra-articular proximal tibial fractures. The knee is positioned in 20° of flexion to neutralise traction forces secondary to the quadriceps muscle, thus preventing an apex anterior angulation of the proximal fragment. An additional advantage of the technique is that it allows the surgeon to avoid or minimise further soft tissue damage because of the distance between the optimal incision point and the usual area of soft tissue damage.

Intramedullary Tibial Nailing Reduces the Attachment Area and Ultimate Load of the Anterior Medial Meniscal Root: A Potential Explanation for Anterior Knee Pain in Female Patients and Smaller Patients

BACKGROUND

Intramedullary (IM) nailing is the treatment of choice among orthopaedic surgeons for tibial shaft fractures. However, because of the close proximity of the nail's insertion site to the anterior medial (AM) meniscal root on the tibial plateau, there is increased risk of iatrogenic injury to the meniscal root during nailing.

PURPOSE

To quantify the area of the AM meniscal root footprint damaged by IM tibial reaming and determine its subsequent effects on the ultimate failure load in female versus male knees.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twelve matched pairs (6 male and 6 female pairs; average age, 50.2 years) of human cadaveric knees were randomly assigned to native and reamed groups. In the reamed group, knees were reamed within the "safe zone" according to current guidelines for IM tibial nail insertion (3 mm lateral to the center of the tibial tubercle and adjacent to the anterior margin of the tibial plateau). The attachment areas and ultimate failure load were quantified and compared with paired knees in the native group.

RESULTS

Intra-articular reaming within the "safe zone" for IM tibial nail insertion did not significantly decrease the AM root attachment area or ultimate failure load in male specimens, as only 2 of the 6 knees were damaged by reaming. In contrast, all 6 of the AM roots in the female knees were damaged by reaming, and on average, reaming decreased the female AM root attachment area by 19% and significantly decreased ultimate failure load by 37% (P = .028). There was a strong negative correlation (R(2) = 0.77) between reamed tunnel-AM root overlap area and medial-lateral width in female but not in male knees.

CONCLUSION

Standard reaming for an IM tibial nail induced significant damage to the AM meniscal root in smaller, female specimens, whereas larger, male specimens were not affected.

CLINICAL RELEVANCE

These findings may suggest that improvements in current guidelines and surgical techniques are warranted to prevent iatrogenic injury to the AM meniscal root during intramedullary reaming for tibial shaft fractures in females and in smaller patients.

[Suprapatellar approach to tibial medullary nailing with electromagnetic field-guided distal locking]

Closed tibial shaft fractures are the domain of intramedullary nailing. With the introduction of new nail designs and technologies, even small, dislocated distal fragments can be anatomically aligned and safely fixed. Unsolved or to a lesser degree controlled are the problems of distal locking in the freehand technique, which can still be difficult and can lead to a significant radiation exposure, and how to control very short proximal tibial fragments in metaphyseal tibial fractures or tibial segmental fractures, where the proximal fracture line also runs through the metaphysis.By using a suprapatellar approach, i.e. a skin incision proximal to the patella with an entry point into the tibial bone from within the knee at the same site as for a standard infrapatellar approach, and then nailing the tibia in a semi-extended position, i.e. the knee is only flexed 10-20°, the intraoperative dislocation of a short proximal fragment can be avoided. The main indications for semi-extended tibial nailing are a short diaphyseal fragment in an isolated tibial shaft fracture, a segmental fracture where the proximal fracture line is metaphyseal and in patients where infrapatellar soft tissues are compromised.The use of the electromagnetic guidance system SureShot® generates reliable and reproducible results, reduces the operating time and is independent from radiation for distal locking.

Controversies in the intramedullary nailing of proximal and distal tibia fractures

Management of tibia fractures by internal fixation, particularly intramedullary nails, has become the standard for diaphyseal fractures. However, for metaphyseal fractures or those at the metaphyseal-diaphyseal junction, choice of fixation device and technique is controversial. For distal tibia fractures, nailing and plating techniques may be used, the primary goal of each being to achieve acceptable alignment with minimal complications. Different techniques for reduction of these fractures are available and can be applied with either fixation device. Overall outcomes appear to be nearly equivalent, with minor differences in complications. Proximal tibia fractures can be fixed using nailing, which is associated with deformity of the proximal short segment. A newer technique-suprapatellar nailing-may minimize these problems, and use of this method has been increasing in trauma centers. However, most of the data are still largely based on case series.

Semiextended intramedullary nailing of the tibia using a suprapatellar approach: radiographic results and clinical outcomes at a minimum of 12 months follow-up

OBJECTIVE

To evaluate the clinical and radiographic results associated with the use of a percutaneous suprapatellar (SP) portal and accompanying instrumentation for tibial intramedullary nail (IMN) insertion using a semiextended approach.

DESIGN

Prospective, nonrandomized, nonconsecutive study.

SETTING

Level 1 trauma center.

PATIENTS AND METHODS

From June 2007 to January 2011, 56 fractures (55 patients) underwent intramedullary nailing of a tibia fracture with a semiextended approach through a SP portal. Radiographic and clinical follow-up examinations were performed at a minimum of 1 year after the index procedure. Measurements included bone healing, tibial alignment, knee range of motion, pain drawings, pain scoring (visual analogue scale), functional outcome (Lysholm and SF-36 scoring), evaluation of prenail and postnail insertion arthroscopic images of the patella-femoral (PF) joint (subgroup of study patients), and 1-year follow-up magnetic resonance imaging (MRI) scans (STIR and T2 gradient echo) of the knee to evaluate the PF joint cartilage. MRI scans were reviewed by an independent bone radiologist, whereas arthroscopic images were evaluated by an independent sports medicine fellowship-trained orthopaedic surgeon.

RESULTS

Thirty-six patients (37 fractures) were available for follow-up at a minimum of 1 year (range: 12-49 months) after the index procedure. All but 2 fractures healed after the index procedure (94.6%). There was 1 radiographic malunion (2.7%). The mean Lysholm knee score was 82.14. Mean SF-36 physical and mental scores were 40.8 and 46.0, respectively. Mean arc of knee motion was 124.4 degrees for the affected extremity compared with 127.2 degrees for the contralateral knee. One patient (2.7%) complained of mild pain at the scar, but no patient complained of anterior knee pain either at the PF joint or at the anterior proximal tibia. In 13 of 15 patients undergoing an arthroscopic assessment of the PF joint, prenail and postnail insertion, no cartilage changes, or pressure points were seen either at the patella or at the trochlea groove. Two patients had grade II chondromalacia of the trochlea immediately after the procedure, but these did not correspond with either MRI scans or clinical findings at 1 year. When the remainder of the 1-year MRI scans were reviewed, 1 knee (2.7%) in a patient that did not have an arthroscopic examination was found to have grade II chondromalacia in the PF joint, but this did not correlate with the clinical examination, which was normal.

CONCLUSIONS

This is the first paper to critically document clinical and radiographic results using the percutaneous SP portal with the semiextended approach for IMN of the tibia. Our 1 year results indicate that the procedure resulted in excellent tibial alignment, union, and knee range of motion, with rare sequelae in the PF joint based on immediate arthroscopy and 1-year MRI scans and clinical examinations. Even more interesting was the absence of anterior tibial pain often found when a tibial nail is inserted in a standard fashion.

Retropatellar nailing and condylar bolts for complex fractures of the tibial plateau: technique, pilot study and rationale

In a previous study, condylar compression bolts and intramedullary nailing with the use of a traditional transpatellar tendon approach were employed for the management of non-impacted complex fractures of the tibia plateau. However, there were intra-operative difficulties, related to the surgical approach that could jeopardise fracture reduction and contribute to sub-optimal outcomes. The purpose of this study is to introduce the retropatellar approach for the management of complex tibial plateau fractures with intramedullary nailing and condylar compression bolts that avoid the pitfalls created by the traditional transpatellar approach.

Semiextended intramedullary nailing of the tibia using a suprapatellar approach: radiographic results and clinical outcomes at a minimum of 12 months follow-up

OBJECTIVE

To evaluate the clinical and radiographic results associated with the use of a percutaneous suprapatellar (SP) portal and accompanying instrumentation for tibial intramedullary nail (IMN) insertion using a semiextended approach.

DESIGN

Prospective, nonrandomized, nonconsecutive study.

SETTING

Level 1 trauma center.

PATIENTS AND METHODS

From June 2007 to January 2011, 56 fractures (55 patients) underwent intramedullary nailing of a tibia fracture with a semiextended approach through a SP portal. Radiographic and clinical follow-up examinations were performed at a minimum of 1 year after the index procedure. Measurements included bone healing, tibial alignment, knee range of motion, pain drawings, pain scoring (visual analogue scale), functional outcome (Lysholm and SF-36 scoring), evaluation of prenail and postnail insertion arthroscopic images of the patella-femoral (PF) joint (subgroup of study patients), and 1-year follow-up magnetic resonance imaging (MRI) scans (STIR and T2 gradient echo) of the knee to evaluate the PF joint cartilage. MRI scans were reviewed by an independent bone radiologist, whereas arthroscopic images were evaluated by an independent sports medicine fellowship-trained orthopaedic surgeon.

RESULTS

Thirty-six patients (37 fractures) were available for follow-up at a minimum of 1 year (range: 12-49 months) after the index procedure. All but 2 fractures healed after the index procedure (94.6%). There was 1 radiographic malunion (2.7%). The mean Lysholm knee score was 82.14. Mean SF-36 physical and mental scores were 40.8 and 46.0, respectively. Mean arc of knee motion was 124.4 degrees for the affected extremity compared with 127.2 degrees for the contralateral knee. One patient (2.7%) complained of mild pain at the scar, but no patient complained of anterior knee pain either at the PF joint or at the anterior proximal tibia. In 13 of 15 patients undergoing an arthroscopic assessment of the PF joint, prenail and postnail insertion, no cartilage changes, or pressure points were seen either at the patella or at the trochlea groove. Two patients had grade II chondromalacia of the trochlea immediately after the procedure, but these did not correspond with either MRI scans or clinical findings at 1 year. When the remainder of the 1-year MRI scans were reviewed, 1 knee (2.7%) in a patient that did not have an arthroscopic examination was found to have grade II chondromalacia in the PF joint, but this did not correlate with the clinical examination, which was normal.

CONCLUSIONS

This is the first paper to critically document clinical and radiographic results using the percutaneous SP portal with the semiextended approach for IMN of the tibia. Our 1 year results indicate that the procedure resulted in excellent tibial alignment, union, and knee range of motion, with rare sequelae in the PF joint based on immediate arthroscopy and 1-year MRI scans and clinical examinations. Even more interesting was the absence of anterior tibial pain often found when a tibial nail is inserted in a standard fashion.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Radiologic outcome and patient-reported function after intramedullary nailing: a comparison of the retropatellar and infrapatellar approach

OBJECTIVES

The purpose of this study was to compare the patient-reported functional outcomes after intramedullary nailing of the tibia through a retropatellar or infrapatellar approach. Radiographic assessment of nail entry point and accuracy of fracture reduction were included to aid in the identification of variables that may explain any difference in patient-reported outcomes.

DESIGN

A retrospective radiographic and questionnaire-based assessment of patient-reported outcomes and complications after tibial nailing for trauma or limb reconstruction through a retropatellar or infrapatellar approach.

SETTING

Regional limb reconstruction unit within a university teaching hospital.

PATIENTS/PARTICIPANTS

Two consecutive series of 38 patients with intramedullary tibial nails inserted through a retropatellar approach, and 36 patients with a tibial nail inserted through an infrapatellar approach.

INTERVENTION

Tibial nail insertion through either a retropatellar or infrapatellar approach.

MAIN OUTCOME MEASURES

Patient-reported outcomes and complication rates and radiographic assessment of fracture reduction and nail insertion entry point.

RESULTS

No significant difference was seen in Kujala score as a measure of anterior knee pain (P = 0.217), either in the physical (P = 0.372) or mental (0.504) components of the SF-12 between the groups, although there was a trend toward symptomatic intrusive knee pain in the infrapatellar group. A more accurate fracture reduction, both in terms of angulation (P = 0.003) and translation (P = 0.010) in the coronal plane, was seen in the retropatellar group. The entry point for nail insertion was more accurate in both the sagittal (P = 0.011) and coronal (P = 0.014) planes.

CONCLUSIONS

Retropatellar tibial nail insertion is not associated with more anterior knee pain when compared with infrapatellar nail insertion but is associated with more accurate nail insertion and fracture reduction.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Comparison of insertional trauma between suprapatellar and infrapatellar portals for tibial nailing

The purpose of this study was to determine differences in insertional articular trauma in infrapatellar tibial portal and suprapatellar portal intramedullary tibial nail insertion techniques. A cadaveric study was performed on 10 matched pairs of fresh-frozen adult cadaver lower extremities with intact extensor mechanisms. Two study groups with 10 limbs each were created: left lower limbs were treated with a standard medial parapatellar nailing portal and right lower limbs were treated with a suprapatellar tibial nailing portal. Start points were created under fluoroscopic guidance in anteroposterior and mediolateral planes. A start wire was placed and opening reaming was performed on the specimens using instrumentation specific to the nailing portal. Specimens were then dissected by medial parapatellar arthrotomy, revealing the intra-articular condition of the knee structures. The border of the tibial entry reamer hole was measured to the anterior horns of the menisci, anterior cruciate ligament root, and intermeniscal ligament using a digital caliper accurate to 0.02 mm. The structure was considered damaged if the structure was obviously damaged on visual inspection or if a measurement was less than 1 mm. Impact to intra-articular structures was numerically lower in the suprapatellar group (2/10) compared with the infrapatellar group (4/10), but the difference was not statistically significant between the 2 groups (P=.629). The suprapatellar portal approach to the tibial start point demonstrated a lower overall incidence of damage to intra-articular structures, but no significant statistical difference existed between the 2 treatment groups.

Quantification of anterior cortical bone removal and intermeniscal ligament damage at the tibial nail entry zone using parapatellar and retropatellar approaches

OBJECTIVES

Anterior cortical bone removal at the tibial nail entry zone has been shown to alter biomechanical properties of the proximal tibia. However, no study has quantified the amount of bone removed. The purpose of this study was to quantify the amount of anterior bone removed at the nail entry zone and assess damage to adjacent intra-articular structures using both parapatellar and retropatellar techniques.

METHODS

The study was performed using 36 cadaveric knees (18 medial parapatellar and 18 retropatellar approaches). A guide pin was placed in the anatomic safe zone using fluoroscopic guidance and a 12.5-mm entry reamer used to open medullary canal. Soft tissues were removed, damage to intra-articular structures recorded, and size of osseous defect created in proximal tibia measured.

RESULTS

The surface area of bone removed with portal creation was not significantly larger with retropatellar (228.4 ± 38.1 mm) versus parapatellar technique (207.9 ± 33.4 mm(2); P = 0.108). This was substantially different than if the entry hole was perfectly round (122.7 mm(2)). No knee went without some damage to intra-articular structures using the parapatellar technique, as opposed to 33% knees with retropatellar technique (P = 0.019). Intermeniscal (IM) ligament was damaged in 83% parapatellar and 56% retropatellar knees (P = 0.146).

CONCLUSIONS

A substantial amount of anterior bone is removed during nail entry portal creation using both parapatellar and retropatellar techniques. Intra-articular structure damage, most commonly IM ligament disruption, was also found to occur at a lower rate with retropatellar technique. Avoidance of both anterior bone removal and IM ligament damage may not be possible because of size and geometrical constraints.

Biomechanical effects of the nail entry zone and anterior cortical bone loss on the proximal tibia

OBJECTIVES

The aims of this study were as follows: to determine if the presence of the nail entry zone alters the biomechanics of the proximal tibia after intramedullary (IM) nailing using a computational model; to determine if nail removal restores normal biomechanics to the proximal tibia; and to determine if these effects are magnified with anterior cortical bone loss.

METHODS

Three-dimensional finite element (FE) tibial models were developed and used for this study: an intact tibia, a nailed tibia, and a tibia with the nail removed. One matched pair of fresh-frozen cadaver tibias was obtained to construct and validate the FE model. The tibias underwent computed tomography scanning, and geometric models were obtained from computed tomography data through volumetric reconstruction. The left tibia was implanted with an unlocked IM nail. The experimental validation of the models was performed by comparing experimental and FE data. Anterior cortical bone of the proximal tibia was removed down to the tibial tubercle on the models to simulate a worst-case scenario of its removal during an IM nailing procedure. Three load cases were considered for each FE tibial model: standing, walking, and single-limb kneeling.

RESULTS

The principal strain values of the proximal tibia with the nail entry zone were increased in comparison to the intact tibia in all 3 loading scenarios (+350%-550%). These effects were greatly magnified with anterior cortical bone loss near the nail entry zone (6-fold increase). The presence of the nail increased the principal strain values in the proximal tibia both with an intact and a disrupted anterior cortex in all loading scenarios, and these values remain elevated even with removal of the nail. The values predicted by the FE model were in good agreement with the experimentally measured strains (R = 0.92).

CONCLUSION

The nail entry zone in the proximal tibia greatly increases the principle strain values when standing, walking, and kneeling. The presence of the nail results in the highest strain values, but they do not return to normal when the nail is removed. These effects are significantly amplified with removal of the anterior tibial cortex near the nail entry zone.

Intramedullary nailing of extra-articular proximal tibia fractures

Tibial fractures are the most common long bone fractures. Extra-articular proximal tibia fractures account for approximately 5% to 11% of all tibial shaft fractures. The benefits of intramedullary nailing of these fractures include load sharing, sparing of the extraosseous blood supply, and avoidance of additional soft-tissue dissection, thereby minimizing the risk of postoperative complications. A significant rate of malalignment has been reported with intramedullary nailing of proximal tibia fractures, however. Malalignment typically presents as apex anterior and valgus angulation. Several nailing methods and reduction techniques have been developed to minimize this complication, including the use of a proper starting point and insertion angle, blocking screws, unicortical plates, a universal distractor, and alternative positioning and approaches. Use of one or more of these techniques has resulted in a reported average malreduction rate of 8.2%.