Nerve Pain After Knee or Hip Replacement: The Overlooked Diagnosis
Persistent pain after knee or hip replacement isn't always the implant. Dr. Brian Kelley, an Austin nerve surgeon, explains the overlooked nerve diagnosis — infrapatellar saphenous neuroma after knee replacement, meralgia paresthetica after hip replacement, and peroneal nerve injury causing foot drop. Covers how to tell nerve pain from mechanical joint problems, why ruling out the joint comes first, who benefits from surgery, and an honest look at the evidence.
Written by Brian P. Kelley, MD — Dual Board-Certified Plastic & Hand Surgeon
Affiliate Faculty Professor, Dell Medical School at The University of Texas at Austin
Seton Ascension Institute for Reconstructive Plastic and Hand Surgery — Austin, Texas
Medically reviewed: June 20, 2026 · Last updated: June 20, 2026
Educational content. Not a substitute for individualized medical evaluation.
Introduction
Joint replacement is one of the most successful operations in modern medicine. Most patients who undergo knee or hip replacement get excellent relief of their arthritis pain and return to active lives, but a meaningful minority continue to have pain afterward — and some of them have a cause that is frequently overlooked.
Up to 20% of patients remain dissatisfied after total knee replacement, often because of residual pain. For a subset of these patients, the pain is not coming from the joint, the implant, or the bone. It is coming from an injured nerve.
This matters because nerve pain after joint replacement is treatable — but only if it is correctly identified. Patients who have a nerve problem are sometimes told their pain is unexplained, or are put through repeated joint-focused workups that don't find an answer, because the nerve diagnosis was never considered.
I practice as a dual board-certified plastic and hand surgeon in Austin, Texas, with fellowship training in hand and microsurgery and a focused practice in peripheral nerve surgery. I take referrals from across Central Texas for persistent post-surgical pain, including nerve pain after joint replacement. My published work includes a co-authored study on regenerative peripheral nerve interface (RPNI) for symptomatic neuromas,1 and a first-author systematic review on postoperative pain in hand surgery.2
This post explains the specific nerves involved, how to tell nerve pain from other causes, why ruling out the joint itself comes first, and what realistic treatment looks like.
The Most Important First Step: Rule Out the Joint
Before any nerve diagnosis is made, the joint replacement itself must be evaluated and the common mechanical causes of pain excluded. This is the single most important principle in this entire discussion.
Persistent pain after joint replacement has a well-defined differential diagnosis that the orthopedic surgeon evaluates first: implant loosening, infection, instability, malalignment, polyethylene wear, fracture, and (after knee replacement specifically) patellar problems or arthrofibrosis. Some of these are serious and require their own treatment, and none should be missed by jumping prematurely to a nerve diagnosis.
A nerve diagnosis is appropriately made only after the joint itself has been evaluated and the mechanical causes have been reasonably excluded. In every published series of successful nerve surgery for post-arthroplasty pain, the patients had component loosening, malalignment, instability, and infection systematically ruled out before nerve treatment was undertaken.
The practical implication: if you have persistent pain after joint replacement, the conversation starts with your orthopedic surgeon. The quality and position of the implant should be assessed, infection should be excluded, and the mechanical causes should be addressed or ruled out. Only then does a peripheral nerve evaluation make sense. A good nerve surgeon will insist on this sequence and will coordinate with your orthopedic team rather than working around them.
Why Nerves Get Injured During Joint Replacement
Joint replacement involves incisions, retraction, and work near nerves that run close to the operative field. Several mechanisms can injure a nerve: direct cutting during the incision or exposure, stretching from retraction or limb positioning, compression from swelling or hardware, and entrapment in scar tissue as the surgical site heals.
Most nerve injuries during well-performed joint replacement are unavoidable consequences of operating in the area, not errors. The infrapatellar branch of the saphenous nerve, for example, crosses directly through the standard midline knee incision and is transected in a high proportion of knee replacements — this is an anatomic reality, not a surgical mistake.
The key point is that some patients tolerate these nerve injuries with only numbness, while others develop persistent, treatable pain. Understanding which nerves are involved helps identify who has a treatable nerve problem.
The Specific Nerves Involved
Infrapatellar Saphenous Nerve (Knee Replacement)
The infrapatellar branch of the saphenous nerve is the single most-frequently-injured nerve in knee surgery. It crosses the standard midline knee incision and is transected or stretched in a high proportion of total knee replacements — anterior knee paresthesia (numbness or altered sensation) has been reported in 55% to 100% of patients after the operation.
Most patients with a transected infrapatellar saphenous nerve have only an area of numbness over the medial or anterior knee. A subset, however, develop a painful neuroma at the cut end. One retrospective review found that up to 9.7% of primary knee replacements and up to 21% of revision cases exhibited persistent knee pain attributable to neuroma formation.3
The pain of an infrapatellar saphenous neuroma is typically focal, with a specific trigger point along the medial or anterior knee where pressure or tapping reproduces sharp, burning, or electric pain (a positive Tinel sign). It sometimes radiates and can be associated with a sensation of knee stiffness. In fact, neuroma pain has been reported as a cause of reversible knee stiffness ("pseudoarthrofibrosis") that resolves when the neuroma is treated.3
Lateral Femoral Cutaneous Nerve / Meralgia Paresthetica (Hip Replacement)
The lateral femoral cutaneous nerve (LFCN) supplies sensation to the skin of the outer thigh. When it is injured or compressed, the result is meralgia paresthetica. This may feel like burning, numbness, tingling, or pain over the anterolateral thigh.
Meralgia paresthetica has become more common with the rising popularity of the direct anterior approach to hip replacement, because that approach passes near the LFCN. Some degree of LFCN disturbance is reported in a substantial proportion of direct anterior hip replacements though in many patients it is a transient sensory disturbance that is slow to resolve rather than a permanent problem.
The general population incidence of meralgia paresthetica is approximately 32.6 per 100,000 patient-years, and it is more common with increasing age, obesity, and diabetes.
The symptoms are sensory only as the LFCN has no motor function, so meralgia paresthetica does not cause weakness. The pain is typically a burning or tingling discomfort over the outer thigh, often worse with standing or walking and sometimes relieved by sitting.
Common Peroneal Nerve (Knee Replacement)
The common peroneal nerve runs along the outer side of the knee and controls the muscles that lift the foot and toes. Injury to this nerve after knee replacement is uncommon but serious. Symptoms can cause foot drop (inability to lift the foot), sensory loss over the top of the foot, and neuropathic pain.
The reported incidence of common peroneal nerve palsy after knee replacement is approximately 0.3% to 4%, with a large systematic review finding a cumulative incidence of about 0.4%.4 Risk factors include a preoperative valgus (knock-knee) deformity, a flexion contracture, epidural anesthesia, higher body mass index, and diabetes.
Common peroneal nerve palsy is the one post-arthroplasty nerve problem that demands urgent attention, because motor function is at stake. Unlike sensory neuromas, where the timeline is more forgiving, a new foot drop after knee replacement should be evaluated promptly.
Other Nerves
Less commonly, the saphenous nerve proper (in the adductor canal of the thigh), the obturator nerve, the femoral nerve, and the sciatic nerve can be involved after hip or knee replacement. These are rarer and the evaluation follows the same principles: confirm the nerve, exclude the joint, and consider the appropriate treatment.
How to Tell Nerve Pain From Other Causes
This is the heart of the diagnostic challenge and requires work-up in concert with your orthopedic surgeon.
Nerve pain is typically neuropathic in quality that may feel like burning, electric, sharp, or shooting, rather than the deep aching of mechanical joint pain. It often has a focal trigger point where pressure reproduces it (a positive Tinel sign), it follows the sensory distribution of a specific nerve, and it is frequently relieved temporarily by a local anesthetic nerve block at the trigger point.
Mechanical joint pain (from loosening, instability, or malalignment) is typically a deep aching pain related to weight-bearing and activity, without a discrete trigger point, and is not relieved by a superficial nerve block. It often correlates with findings on imaging.
Infection typically produces pain with warmth, swelling, redness, sometimes fever, and abnormal inflammatory markers on blood testing. It is excluded with specific tests (ESR, CRP, joint aspiration) and must never be missed.
Referred pain, for example, hip pathology referring pain to the knee, or spine pathology (lumbar radiculopathy) referring pain to the thigh or leg, can mimic both joint and nerve problems and requires its own evaluation.
The single most useful tool for confirming a nerve cause is the diagnostic nerve block: if a small injection of local anesthetic at the suspected nerve temporarily eliminates the patient's typical pain, that strongly supports a nerve diagnosis and predicts that treating that nerve will likely help. A negative block argues against a nerve cause and should prompt reconsideration.
Diagnosis
The diagnosis of post-arthroplasty nerve pain is clinical, supported by selective testing.
A typical history includes pain that began after the joint replacement, has a neuropathic quality, and is localized to a specific nerve distribution. A focused examination identifies the trigger point, maps the sensory distribution, and (for the peroneal nerve) tests motor function.
Diagnostic nerve blocks, often performed under ultrasound guidance, confirm the affected nerve. High-resolution ultrasound can sometimes visualize a neuroma directly. MRI is occasionally useful. Electrodiagnostic testing (EMG/nerve conduction studies) has a role particularly for the peroneal nerve and for distinguishing a nerve problem from a spine-related cause.
Crucially, the diagnostic workup proceeds in coordination with the orthopedic team, so that the joint is being evaluated for mechanical causes at the same time the nerve is being evaluated.
Treatment Options
Treatment ranges from conservative measures to several surgical approaches, depending on the nerve involved, the severity, and the response to non-surgical care.
Conservative Management
Most patients begin with non-surgical treatment: neuropathic pain medications (gabapentinoids, tricyclic antidepressants, duloxetine), topical agents, physical therapy with desensitization, and selective nerve blocks. Many sensory nerve problems improve over time, and some resolve entirely. For meralgia paresthetica in particular, a substantial proportion of cases remit spontaneously or are managed adequately without surgery.
When conservative measures fail to provide adequate relief after a reasonable trial, surgical options enter the conversation.
Surgery for Infrapatellar Saphenous Neuroma
For a confirmed painful neuroma of the infrapatellar saphenous nerve, surgical neuroma excision (often with modern techniques to manage the cut nerve end) is effective in well-selected patients.
A prospective series of 25 patients undergoing neuroma excision for neuromatous knee pain (the infrapatellar saphenous nerve was the most commonly involved nerve, in 24 of 25 patients) reported complete pain relief in 44% and partial relief in 40%, with an overall satisfaction rate of 84% and no patient reporting a worse outcome.5
A separate case series of selective neuroma denervation for the infrapatellar saphenous nerve reported achievement of clinically meaningful improvement on validated patient-reported outcome measures (Oxford Knee Score, SF-12, and pain scores).6
Ultrasound-guided local treatment (hydrodissection and corticosteroid injection) is a non-surgical option that has shown durable pain relief in some patients, and can serve as both a diagnostic and therapeutic step.7
Surgery for Meralgia Paresthetica
For refractory meralgia paresthetica, two surgical options exist: decompression (neurolysis), which releases the nerve while preserving it, and neurectomy, which divides the nerve.
A systematic review and meta-analysis comparing treatments found complete pain relief in 85% of patients after neurectomy, 63% after neurolysis (decompression), and 22% after injection alone — with all three differing significantly, and complication rates of 0% to 5% that were statistically comparable across approaches.8 Neurectomy produces a permanent patch of numbness on the outer thigh, which most patients tolerate well in exchange for pain relief; decompression preserves sensation but has a somewhat lower success rate.
The choice between decompression and neurectomy is individualized, weighing the higher success rate of neurectomy against the sensory loss it produces.
Surgery for Common Peroneal Nerve Palsy
Common peroneal nerve palsy is managed differently because motor function is at stake and the timeline matters. Many incomplete palsies recover on their own. A systematic review found that 66% of incomplete peroneal palsies after knee replacement recovered completely without surgery, while only 39% of complete palsies recovered fully.4
For palsies that do not recover, or in specific situations, surgical decompression (neurolysis) of the common peroneal nerve has been used to improve outcomes. The decision and timing are made in close coordination with the orthopedic and neurology teams, and a new or worsening foot drop warrants prompt evaluation.
Modern Techniques: TMR and RPNI
When a neuroma is excised, the cut nerve end can itself form a new painful neuroma. Two modern techniques address this: targeted muscle reinnervation (TMR), which redirects the cut nerve into a motor branch, and regenerative peripheral nerve interface (RPNI), which wraps the cut end in a small muscle graft.
Both aim to give the regenerating nerve a productive target rather than allowing disorganized neuroma reformation. I frequently incorporate these techniques when treating post-arthroplasty neuromas, and my published work supports their use for symptomatic neuromas.1
Who Benefits — and Who Doesn't
In short, patient selection is the most important determinant of a good outcome.
Patients who benefit typically have: pain with clearly neuropathic features (burning, electric, focal); a positive Tinel sign over a specific nerve; temporary relief from a diagnostic nerve block; a well-functioning joint replacement with mechanical causes excluded; and realistic expectations.
Patients who are less likely to benefit from nerve surgery include those with diffuse, non-focal pain; those whose pain does not respond to diagnostic block; those with an unaddressed mechanical problem with the joint; and those whose pain has a large central sensitization component. For these patients, nerve surgery addresses the wrong target or only one of many issues. In such cases a different approach or multiple approaches may be needed.
This is why the evaluation matters so much. The goal of a good consultation is not to find a reason to operate. Instead, the consultation is to determine accurately whether a treatable nerve problem is present and, if so, to recommend nerve surgery only when evidence supports it.
Limitations and Framing of the Evidence
The published evidence for nerve surgery after joint replacement comes largely from case series and small cohorts rather than large randomized trials. The infrapatellar saphenous neuroma series are mostly retrospective and modest in size. The meralgia paresthetica literature is more developed but still lacks large randomized comparisons. The peroneal nerve decompression evidence is limited and the indications remain debated.
This means two things. First, the reported success rates, though encouraging, come from selected patients at experienced centers, and individual results vary. Second, the decision to operate is individualized and conservative, reserved for patients with clear diagnoses who have failed non-surgical management.
I tell patients honestly that nerve surgery for post-arthroplasty pain can produce meaningful, but that it is not guaranteed. The evidence is still maturing and patient selection is everything.
Recovery and Risks
Recovery from nerve surgery for post-arthroplasty pain is generally straightforward. Neuroma excision and decompression procedures are typically outpatient. The incisions heal over a couple of weeks, restricted activity is usually four to six weeks, and pain relief may begin within weeks and continues to evolve over months.
The risks include the general risks of surgery (bleeding, infection, scarring, anesthetic complications) plus specific considerations: incomplete pain relief despite a technically successful operation, recurrent neuroma formation, sensory loss in the distribution of a divided nerve (intentional with neurectomy), and rarely worsening of pain. For peroneal nerve surgery, motor outcomes are variable.
Related Topics
- Painful neuroma after prior surgery
- Peripheral nerve surgery, RPNI, and TMR
- TMR vs. RPNI: what is the difference?
- Nerve transfers vs. nerve grafts: how surgeons choose
- Chronic groin pain after hernia surgery: when a nerve is the cause
- When to seek a second opinion after nerve surgery
- When your EMG is normal but the pain is real
- Finding a peripheral nerve surgeon in Texas
Frequently Asked Questions
Yes. Joint replacement involves working near nerves, and several nerves can be injured during the operation — most commonly the infrapatellar branch of the saphenous nerve (knee), the lateral femoral cutaneous nerve (hip, causing meralgia paresthetica), and occasionally the common peroneal nerve (knee, which can cause foot drop). Most nerve injuries cause only numbness, but a subset cause persistent, treatable pain.
Nerve pain is typically burning, electric, or sharp, with a specific trigger point where pressure reproduces it, and it often follows a nerve's sensory distribution. Mechanical implant pain is typically a deep ache related to weight-bearing, without a focal trigger point. The most useful test is a diagnostic nerve block: if a small local anesthetic injection temporarily eliminates your pain, that points to a nerve cause. Your orthopedic surgeon should evaluate the implant first to rule out loosening, infection, or malalignment.
Start with your orthopedic surgeon. The first priority is evaluating the joint replacement itself and confirming the implant is well-positioned and well-fixed. They will also exclude infection, loosening, instability, and malalignment. Only after the mechanical causes have been reasonably excluded does a peripheral nerve evaluation make sense. A good nerve surgeon insists on this sequence and coordinates with your orthopedic team.
Meralgia paresthetica is burning, numbness, or tingling over the outer thigh caused by injury or compression of the lateral femoral cutaneous nerve. It has become more common with the direct anterior approach to hip replacement. Because this nerve is purely sensory, meralgia paresthetica causes no weakness. Many cases improve on their own or with conservative treatment. Refractory cases can be treated with nerve decompression or neurectomy though success is not guaranteed.
The infrapatellar branch of the saphenous nerve crosses the standard knee replacement incision and is frequently cut during the operation. Most patients have only numbness, but some develop a painful neuroma at the cut end. This may produce focal, burning or electric pain along the medial or anterior knee with a specific trigger point. It is an underrecognized cause of persistent knee pain after replacement, and it can be treated with neuroma surgery or ultrasound-guided injection in appropriate patients.
Foot drop after knee replacement suggests an injury to the common peroneal nerve, which controls the muscles that lift the foot. This is an uncommon but serious complication that warrants prompt evaluation. Many incomplete peroneal palsies recover on their own over months, but complete palsies have a lower rate of full recovery. Surgical decompression is considered in specific situations. A new or worsening foot drop should be evaluated quickly by your surgical team.
In well-selected patients, success rates are encouraging. Published series of infrapatellar saphenous neuroma excision report 64% excellent and 20% good outcomes with substantial pain score improvement. Meralgia paresthetica neurectomy produces complete pain relief in about 85% of patients. However, these results come from selected patients at experienced centers, the evidence base is largely case-series-level, and individual results vary. Patient selection, confirmed by examination and diagnostic block, is the strongest predictor of success.
Possibly. Some pain and altered sensation after joint replacement is part of normal recovery and improves over months, particularly numbness around the incision. The concern is persistent, neuropathic-quality pain that limits function and does not improve on the expected timeline. If your pain is focal, burning or electric, and not improving, evaluation for a nerve cause (after the joint has been assessed) is reasonable.
As a fellowship-trained hand and peripheral nerve surgeon in Austin, I see patients from across Central Texas for evaluation of post-arthroplasty nerve pain, working in coordination with orthopedic surgeons. Referrals from orthopedic surgery, primary care, pain medicine, and physical medicine and rehabilitation are welcome, and direct patient inquiries are accepted depending on individual insurance plans.
1. Hooper RC, Cederna PS, Brown DL, Haase SC, Waljee JF, Egeland BM, Kelley BP, Kung TA. Regenerative Peripheral Nerve Interfaces for the Management of Symptomatic Hand and Digital Neuromas. Plastic and Reconstructive Surgery — Global Open. 2020;8(6):e2792. PMID: 32766027.
2. Kelley BP, Shauver MJ, Chung KC. Management of Acute Postoperative Pain in Hand Surgery: A Systematic Review. Journal of Hand Surgery (American). 2015;40(8):1610–1619. PMID: 26213198.
3. Kachar SM, Williams KM, Finn HA. Neuroma of the infrapatellar branch of the saphenous nerve: a cause of reversible knee stiffness after total knee arthroplasty. Journal of Arthroplasty. 2008;23(6):927–930. DOI: 10.1016/j.arth.2007.07.019.
4. Carender CN, Bedard NA, An Q, Brown TS. Common Peroneal Nerve Injury and Recovery after Total Knee Arthroplasty: A Systematic Review. Arthroplasty Today. 2020;6(4):662–667. PMID: 32875016.
5. Nahabedian MY, Johnson CA. Operative management of neuromatous knee pain: patient selection and outcome. Annals of Plastic Surgery. 2001;46(1):15–22. PMID: 11192028.
6. Painful total knee arthroplasty: Infrapatellar branch of the saphenous nerve selective denervation. A case series. The Knee. 2022;38:30–37. DOI: 10.1016/j.knee.2022.07.008.
7. Shi GG, Schultz DS Jr, Whalen J, Clendenen S, Wilke B. Midterm Outcomes of Ultrasound-guided Local Treatment for Infrapatellar Saphenous Neuroma Following Total Knee Arthroplasty. Cureus. 2020;12(1):e6565. PMID: 32042535.
8. Lu VM, Burks SS, Heath RN, Wolde T, Spinner RJ, Levi AD. Meralgia paresthetica treated by injection, decompression, and neurectomy: a systematic review and meta-analysis of pain and operative outcomes. Journal of Neurosurgery. 2021;135(3):912–922. PMID: 33450741.
Closing Disclaimer
This article is educational and does not establish a doctor-patient relationship. It does not replace individualized consultation, examination, or review of personal medical history. Patients with persistent pain after joint replacement are encouraged to begin with their orthopedic surgeon to evaluate the joint, and to seek peripheral nerve evaluation when a nerve cause is suspected after mechanical causes have been excluded.
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