Correlations of typical pain patterns with SPECT/CT findings in unhappy patients after total knee arthroplasty.

PURPOSE: The diagnostic process in patients after painful total knee arthroplasty (TKA) is challenging. The more clinical and radiological information about a patient with pain after TKA is included in the assessment, the more reliable and sustainable the advice regarding TKA revision can be. The primary aim was to investigate the position of TKA components and evaluate bone tracer uptake (BTU) using pre-revision SPECT/CT and correlate these findings with previously published pain patterns in painful patients after TKA. METHODS: A prospectively collected cohort of 83 painful primary TKA patients was retrospectively evaluated. All patients followed a standardized diagnostic algorithm including 99m-Tc-HDP-SPECT/CT, which led to a diagnosis indicating revision surgery. Pain character, location, dynamics and radiation were systematically assessed as well as TKA component position in 3D-CT. BTU was anatomically localized and quantified using a validated localization scheme. Component positioning and BTU were correlated with pain characteristics using non-parametric Spearman correlations (p < 0.05). RESULTS: Based on Spearman's rho, significant correlations were found between pain and patients characteristics and SPECT/CT findings resulting in nine specific patterns. The most outstanding ones include: Pattern 1: More flexion in the femoral component correlated with tender/splitting pain and patella-related pathologies. Pattern 3: More varus in the femoral component correlated with dull/heavy and tingling/stinging pain during descending stairs, unloading and long sitting in patients with high BMI and unresurfaced patella. Pattern 6: More posterior slope in the tibial component correlated with constant pain. CONCLUSION: The results of this study help to place component positioning in the overall context of the "painful knee arthroplasty" including specific pain patterns. The findings further differentiate the clinical picture of a painful TKA. Knowing these patterns enables a prediction of the cause of the pain to be made as early as possible in the diagnostic process before the state of pain becomes chronic. LEVEL OF EVIDENCE: Level III.

Typical Pain Patterns in Unhappy Patients After Total Knee Arthroplasty.

BACKGROUND: The primary aim of this study is to assess characteristics of pain in patients with ongoing pain after total knee arthroplasty (TKA). The secondary aim of this study is to identify specific pain patterns and link these to underlying pathologies. METHODS: A prospectively collected cohort of 97 painful primary TKA patients was retrospectively evaluated. All patients followed a standardized diagnostic algorithm, which led to a diagnosis that set the indication for revision surgery. Character, location, dynamics, and radiation of pain were systematically assessed and correlated with the underlying pathologies. RESULTS: Most frequent pain characters were pricking/lancinating (45.7%), pinching/crushing, and dull/heavy (38.6%); 89.5% of all patients localized their knee pain anteriorly; 48.1% reported pain aggravations by descending stairs. Radiating pain was reported in 14% of the patients. Patella-related problems (56.7%) and instability (52.6%) were the most frequent pathologies. Based on correlations between the characteristics 6 specific pain patterns were identified. The most outstanding ones include the following: pattern 1, instability is associated with jumping/shooting, pricking/lancinating and tugging/wrenching pain, and aggravated by chair raising and starting; pattern 6, pain aggravation by descending stairs is associated with anterior and lateral jumping/shooting, tingling/stinging and sharp/lacerating pain character, and TKA positioning and patella baja. CONCLUSION: The assessment of painful TKA patients involving specific pain patterns help to further differentiate and define the clinical picture and ultimately the cause of a painful TKA. If the causes of the described complaints are known, a decision for a therapy can be made reliably and sustainably at an early stage before the state of pain becomes chronic.

Cranioplasty following decompressive craniectomy: minor surgical complexity but still high periprocedural complication rates.

Cranioplasty following decompressive craniectomy is of low surgical complexity, so much so that it has become the "beginners" cranial case. However, these "simple" procedures may have high complication rates. Identification of specific risk factors would allow targeted intervention to lower the complication rates. The aim of this study was to assess the rate of complications and to evaluate potential risk factors. We conducted a review of all patients who underwent cranioplasty in our center following decompressive craniectomy for stroke or brain trauma between 2009 and 2016. One hundred fifty-two patients were identified. Fifty-three percent were male. Mean age was 48 (range 11-78). Median time from craniectomy until cranioplasty was 102 days (range 14-378). The overall rate of complications, such as postoperative bleeding, seizures, postoperative infection, and hydrocephalus, was 30%. The mortality rate was 1%. None of the following potential risk factors was associated with significantly increased risk of periprocedural complications: gender (p = 0.34), age (p = 0.39), cause of initial surgery (p = 0.08), duration of surgery (p = 0.59), time of surgery (0.24), surgical experience (p = 0.17), and time from craniectomy until cranioplasty (p = 0.27). The 30-day complication rate following cranioplasty is high, but serious permanent deficits from these complications were rare. We found no clear predictor for these 30-day complications, which renders its prevention difficult.