The Wings of Ilium

I'm not the only one to take an interest, everyone seems to be stealing glances at my wife, who is blushing, but avoiding eye contact with the students by staring at me with a poker face. If the rest of us were wearing scrubs, and standing on linoleum instead of carpet, it might be just another day at the hospital, but in these circumstances, it was surreal; Katherine was definitely the odd one out in her gown.

After an awkward pause in proceedings, I realize I need to keep the session moving. I reach under the table to grab the towel and place it on top before asking Katherine to lie on the table, face down.

The tabletop comes up to my hip, it's not something Katherine can modestly lean down onto, so there's some climbing and kneeling and shifting of gown required for Kath to orient herself. The lowest of the three gown ties is just about where her lumbar curve becomes the sacral curve, so Katherine's beautiful ass is suddenly on display in only her briefs. I notice she has moved the towel while mounting the table, and is now using it as a pillow. I guess she doesn't need a modesty cover.

As Kath settles onto the table, TB makes a quiet whistle and says, "Mighty fine," Nick and Ryan both smile back at him, nodding. Sarah pokes Nick with her elbow, shaking her head in amusement, while Sean makes eye contact with me and gives me the double-thumbs-up, mouthing something I can't decipher, but is obviously along the lines of 'excellent choice' or something. It's clear he doesn't know he's complimenting my wife's bum.

I hand the skin pen to Nick. "Okay, Bart," I say, "I want you to write out all the vertebrae on the blackboard," as I gesture towards Katherine. TB looks hurt, and jealous, as he realizes the 'punishment' I've just given Nick for his goof in the ER.

I'm hoping it'll be a blessed punishment for Katherine, too - her lower back is an erogenous zone, along with her ears, plus the more typical neck, breasts, inner thighs, vagina, and anus. I'm feeling bad about boring her at the start of the session. Hopefully, this will keep her playful mood going, until I can get her back to the hotel bed.

I decide to bring the group a few steps away from the table (and my exposed wife). Nick is left-handed so has moved to the far side. He leans in close to Katherine to ask something, which gets a nod, then he straightens up and undoes the three string ties on the gown. He begins by walking his fingers down Kath's spine in a counting manner - good, he's remembered that not everyone has the same number of vertebrae.

With difficulty, I continue my talk about the other set of pelvic muscle attachments. Those that go upwards to action the torso. My students also seem a little distracted, with fairly regular glances back towards the massage table.

Nick isn't listening to me, he seems to be entertaining Katherine with whispered conversation or jokes, in between working on his masterpiece. He often has his whole forearm resting on Katherine, while stabilizing the 'canvas' with his right hand. In the lumbar region, this means he was resting his arm across her buttocks. He even pulls the elastic of her briefs down at one point, to trace out the sacrum and coccyx. I was expecting a simple row of labels; C1 to C1, T1 to T12, and L1 to L5, maybe with a rectangle around each, but Nick is sketching onto Katherine's back an anatomically correct vertebral column, complete with partial ribs.

Speaking to the group, I finish up my review of the skeletal muscles. "Don't forget about the pelvic diaphragm. Most of the medial muscles we've just covered also assist the perineum, as none of the sphincters action in isolation. But we'll return to the pelvic floor in a future session, sometime after we finish the rest of the skeletal sessions - spine, upper limbs, and then neck and skull."

Maybe Nick has been listening to me because as I finish, he pats Kath twice with his fingertips and says, "All done." It wasn't quite a 'pat on the bum,' but only slightly higher than that on the gluteus medius. Katherine arches her back in an attempt to look over her shoulder, her elbows still pressed at her side to hold the untied gown, but her attempt to see the drawing is futile, and she slumps forward with a brief glance towards the group. I try to read her expression, without luck.

Nick replaces the cap on the skin pen and tosses it under the table. He's fully paying attention to me now, but doesn't leave Kath's side. He seems pleased, he's probably waiting for us to come and judge his artwork. Kath has her eyes closed and is blowing air through pursed lips for a few deep breaths. Is that a breathing exercise to calm herself? Has my plan delivered redemption for the earlier boredom I caused? She opens her eyes again, and I see her pupils are dilated, but there's also a frown, some anxiety in her face that's sending a mixed message.

"Any questions?" I ask the students.

"Is that male or female?" Kim says, pointing to the plastic pelvis in my hand.

"Ahh. The osteology is inconsistent. You've probably noticed the large pelvic cavity, but the narrow intercristal distance between the iliac crests. And they've taken some manufacturing shortcuts to articulate the hip, so the ischium is entirely artificial. On balance, I'd have to go with the angle of the sacrum and say it's male, mostly. Let me show you the difference on our live model."

Without further prompting, the group quickly migrates back to the table to admire Nick's anatomically correct artwork. "Da Vinci would be proud," states Sean, summing up the general consensus.

"Can I take a photo?" asks Ryan, not really sure who to address, "...as a study aid," he adds, which does nothing to silence the mirth of the group. Counting vertebrae is something they all mastered in their first year.

"I'd like one," says Nick.

"Yep," adds TB.

Brooke asserts her authority, "I'll be the only one taking any photos. And only if Katherine approves."

"Umm. That'll be okay. I'd like to see it, too," Kath responds, before shifting the towel-cum-pillow a bit with her fingers, so she can hide her face in the hole of the massage table.

Brooke attempts to frame Kath's temporary adornment with outstretched arms, but eventually chooses to climb onto the sturdy table, standing astride Kath's legs.

"Would you mind if we show the full drawing Katherine?" she asks.

Kath responds by straightening her arms down her flanks and hooking her thumbs into the waistband of her underwear. She hitches them down further than is required. Two or three inches of cleft is now exposed below where the penmanship ends on her coccyx. I guess it isn't her near-nudity that troubles her.

Brooke's phone makes the shutter noise twice, and then a third time with the flash enabled.

As she climbs down from the table, Jess is trying to see the screen, but Brooke locks her phone and announces, "I've got all your numbers, I'll send a pic to all of you on the condition you don't forward it. If I find it doing the rounds, I'll be treating it like a breach of patient privacy." I think she's looking out for my interests, and Kath's, setting the rules herself, so I can maintain a guise of detachment from my exposed wife on the table.

"Okay. If we're done?" I resume. "Back to the sexual dimorphism of the pelvis. You'll note Mister Polyethylene here," holding the pelvic model upright, "has a near vertical sacral angle into what's left of his column. Females typically develop a deeper curve through the lumbar set. Studies show that men find fourty-five degrees to be the most attractive. Note that just implanting a big silicone booty doesn't entirely fool men if the lumbar region remains vertical. Men are attracted to a woman's ability to bear children, and the sacral angle is one of the cues they're looking for, subconsciously."

I mimic the contours of Kath's lower spine to tailbone with a sweep of my hand, a few inches above her prone form. "You'll notice Katherine's sacral angle is near that ideal. Coupled with her ilium locating the strong gluteal muscles distal from the birth canal, where they can't harm a baby during delivery. This, of course, is the reason for the wider hips you see on the female pelvis, all combining to be - as Tremaine assesses it - mighty fine." The group laughs, as I recite TB's words, attempting to impersonate his distinctive voice and mannerisms.

"Can you tell if there's been childbirth?" asks Sarah.

"Not necessarily by the pelvis alone," I answer. "Although, during the last trimester the ligaments do significantly loosen in preparation for delivery. But they normalize in a matter of weeks after the birth. You'll have to look at other indicators."

"Such as?" prompts Ryan.

"Well, let's think it through... Could you turn over please, Katherine?"

Kath awkwardly rolls over, still clamping the gown in her armpits to keep her breasts covered. She then flicks the loose ball of material downwards to cover her briefs.

"So, Jess," I continue, choosing her randomly, "your patient is non-responsive and you need to find out if she's a mother. What superficial signs of childbirth might you look for?... Without a vaginal inspection." Thinking she should know about the linea nigra on the abdomen.

Jess steps up to the table next to Brooke. "Possibly a C-section scar?..." I had forgotten about that, around thirty percent of births in the US are Caesarean. She folds the lower half of the gown twice to expose Kath again, up to the navel. Not seeing anything of note, she briefly peeks under Kath's briefs as incisions are commonly made below the bikini line. Kath is slightly startled by the brush of Jess' finger against her skin. I see her eyes open widely to look, but Jess and most of the others are engrossed in the 'challenge' I have set. Kath relaxes again, closing her eyes.

I smell arousal in the air. Specifically Kath's familiar scent, probably wafted by the movement of the gown. She is definitely aroused. I am aroused. That might explain the trepidation I saw earlier, and the awkward roll onto her back. The gusset of Kath's underwear is likely wet and she is dreading the time when I ask her to articulate her lower limbs and expose her secret.

"No pregnancy line..." Jess continues, running her thumb up towards the navel, "but they fade a few months after birth." Running her hand laterally across Kath's abdomen, while bobbing her head to inspect, she announces with a clinical voice, "No obvious stretch marks, but possibly some looseness. Inconclusive. But there does seem to be some diastasis recti indicative of postpartum."

I notice a runic ring on Jess' smallest finger, probably Old Norse writing at a guess, as Vikings seem to be popular on television at the moment. For an instant, I'm pleased it's just a piece of cheap costume jewelry, not an engagement ring, but then I decide I'm being foolish and selfish, I really just want her to be happy.

"Do you mind?" Jess asks, hovering her hands near Kath's shoulders.

Kath's eyes were closed, and perhaps she was dwelling on her sticky situation. Confused by the question, she sits up partially to look, which Jess interprets as cooperation and deftly releases the gown from Katherine's shoulders. She has it down to the elbows, before Kath even realizes what the question was.

I see the brief flash of horror in Katherine's eyes, and open my mouth ready to say something, but I'm trapped by the same dilemma she is. Kath is supposedly a 'nude model' for 'big commercial shoots' and just recently did a 'topless gig,' why would she be shy in front of a few medical students?

My blushing wife looks down to me at the foot of the table. I smile, probably goofily, and give a small shrug. Sometimes when you play silly games, you score an own goal, I guess. Strangely, I'm not upset and can already see the humor of the situation. This will be a great story for years to come, even if it's just between the two of us. And Brooke too, I just realize.

Kath reclines again and briefly doesn't seem to know what to do with her arms. She can't cover her breasts, which would be her natural instinct. She settles for draping her right arm across her face, covering her eyes behind her elbow, and leaving her left arm straight down her flank. There's a small smile on her face now, she can see the humor, too. Meanwhile, Jess has rolled up the gown and disposed of it under the table, unaware of the distress she just sparked.

"With no linea nigra and a firm abdomen, you wouldn't expect the patient to still be lactating, but it would be a strong indicator if she were. Her nipples certainly appear to be fully developed, though." Jess is rolling Kath's left nipple between her fingers, while the rest of the group, myself included, watch in silence, entranced by the caress. And it does seem as much a caress as an examination.

Apart from the now-severely erect nipples, Katherine's breasts are flat across her thorax. In this supine position, the lower costal cartilage - the lower part of her rib cage immediately above the stomach - is more elevated than her flat bosom. The pleasing form of her left breast has migrated laterally while the right, stretched by the raised arm, is nearly imperceptible - the breast tissue only discernible to the touch, or by noting the absence of visible ribs proximal to the nipple.

Jess cups the 'pleasing form' with her hand. "These are very soft. I would guess that's post-breastfeeding ptosis, I don't think the sagging would be from age in a, what, 40 year old?" she asks, with a quick double-squeeze.

"I'm non-responsive," responds Katherine. Good, she still has her sense of humor.

"And she doesn't have an inverted nipple, like Sarah, they don't survive breastfeeding," comments Ryan.

"Excuse me?" responds Sarah, putting her hands on her hips with feigned indignation. "Have you been peeking? Who told you this?"

Ryan's guilty glance at TB answers her question.

"And have you been talking about my breasts, too?" she asks Sean.

Sean embellishes his accent into a 'posh' Brit. "I had not even noticed you had breasts, ma'am. But now you mention them, would you mind putting 'em on show? Come on now, don't be a bore."

The group is laughing, but Jess is intrigued, "Only one side? Seriously? Can you show me, Sarah?" I notice she still has her hand resting on Kath's chest, her thumb slightly deflecting the left nipple."

Sarah pauses briefly to watch Jess, who does appear to be genuinely interested. Years ago at college, I studied insect pheromones in biology - powerful stuff. I have no doubt some kind of neurosteroid was at work here, either the unproven human sex pheremone, or a natural sympathetic response to Kath's scent. The group is bunched around the table as if we hadn't just gone through two years of social distancing, Nick's erection is noticeable (Ryan has loose fitting pants; TB and Sean are currently obscured from my glance). Kim's nipples also appear to be erect, the other women (Sarah, Jess, and Brooke) seem to be wearing bras or thicker clothing. However, they all have the flushed look and dilated pupils I noted on Katherine earlier. The mere fact Sarah is reaching for the buttons on her blouse shows that normal behavior has been warped by this intimacy within the room.

Surprisingly, I am not upset by the sexual tension that's apparently stalking my near-naked wife. It's not that my usual petty jealousy has been cured, more that a unique set of circumstances have conspired to make this seem almost natural. Previously, Kath wouldn't go topless on a sparsely populated beach of strangers. Now, she was showing her body to a close group of my friends, and could even smile about it. And not only showing her body, Jess was still stroking her boob with her fingertips absentmindedly. I should probably resume control of the lesson, but I want to see how this 'science experiment' plays out. Plus, I am as horny as the students are right now.

Sarah reaches behind her back to unclasp her white bra. I get a glimpse of the decorative cups, but from my position at the foot of the table, I mostly see the sheer white panels that make up the wide strap at the back.

"Ta-da!" Sarah announces, as she spreads her arms and flicks her blonde hair behind her shoulders. Apart from Nick and TB, who she dismisses with, "You two have already seen these," she briefly turns to each of us, including me, to show them off, purposely adding a little bounce with each movement. Her breasts are slightly larger than average, probably a C-cup, hosting large, feint areolas with an indistinct boundary. And she does indeed have an inverted nipple on her right-hand side; a vertical crease turning it into an innie rather than an outie. There's probably an anatomical word for it, but I'm not thinking particularly clearly right now.

"Up to ten percent of women have inverted nipples," Sarah announces. "Mine is coming out, as I'm always tweaking it. If you ever see me with my arms crossed, I'm probably squeezing my nipple." She gives a quick demonstration of this revelation - even I have seen her with her arms crossed before.

"It's not a problem, though," Sarah continues. "Sometimes, they grow out during pregnancy, even if they don't, the baby can still latch on. But very few remain inverted after a course of breastfeeding."

"Come, come," says Jess, gesturing with her hand that is finally off Katherine's breast. "Let me feel."

Sarah steps up to the left of Katherine's table, opposite Jess, who reaches across to take the inverted nipple between her fingers. She studies it with a pinch and roll, before moving her hand to the left nipple. Sarah seems amused by the situation, she does like being the center of attention. Her move has triggered a ripple of movement among the rest of the group; everyone wants to watch and the table is now encircled closely. I hold my ground at the foot of the table, and notice Katherine getting a close-up view, peeking up from under her arm.

"They are definitely different. Katherine's nipple has more structure behind them than Sarah's, or my own," says Jess. "Feel them," she encourages Sarah, who is now curious and obliges by taking hold of Katherine's closest nipple for an inspection.

"Are you a mother, Brooke?" asks Jess, apparently on the verge of a great medical discovery, but needing more clinical trials.

"No, Jess, I've never been pregnant," she replies, "but your logic is sound, the breasts don't fully develop until pregnancy. I'm also guessing Katherine is a mother, but let's get a nurse's opinion." Brooke reaches out and takes a hold of my wife's other nipple. A line is almost forming now, half-a-dozen hands waiting to compare the feel of my wife's nipple against Sarah's nipple, or their own."

Throughout this exploration of touch, I'm watching Katherine on the table. Her right arm covers her eyes again. She is breathing faster, exhaling through her mouth, and subtly squirming, pressing her knees together rhythmically. Only I notice. Or is Brooke observant to this also?

There is a lot of tactile exploration going on - Kath's nipples, breast tissue, and abdomen are being gently prodded, manipulated, and palpitated as the students make their own assessment of my misguided challenge; is this 'unresponsive patient' a mother?

It's becoming too much for Katherine. "Uhh... I think I need to take a break," she announces. Her hands are now pressed on her upper sternum, fingers white with the pressure. Her eyes remain closed.

"Are you uncomfortable?" asks Brooke, with concern.

"No, ahh, quite the opposite," she responds falteringly. "I, um, I need... relief."

"Oh," Brooke answers, then pauses, while she and the group digest this new revelation. "There's not really anywhere private. The rest of this floor is locked."